Solar filter

For next year's solar eclipse, I'm aiming to use my 500 f/4 lens. I searched around for solar filters, and came across this one. I'm quite pleased with the whole setup so I thought I'd share. I bought mine in Canada, so you'll just need to search for "Baader solar filter" to find a distributor near you. Note that there are quite a few models, and I spent a fair bit of time going through them all before settling on the ASTF 120 for my lens. It is a perfect fit. It holds on by friction and is quite secure, but it's also easy to pull it off quickly for the total phase of the eclipse.

https://photos.smugmug.com/photos/i-...D5C964x-XL.jpg

https://photos.smugmug.com/photos/i-...9Pf5nHP-XL.jpg

https://photos.smugmug.com/photos/i-...HHFHHzx-XL.jpg

Thanks, Jonathan. Based on your efforts, the 140mm version should work well for the 600/4. B&H sells them (as special order items, with 2-4 week delivery; Google shows other US suppliers with stock on hand). I'll need to decide whether I'm going to take the 600/4, or use the RF 100-300/2.8 with a TC.

My older daughter is very excited about the eclipse, and at her request we are planning to drive up to New Hampshire for the event.

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Originally Posted by neuroanatomist

Thanks, Jonathan. Based on your efforts, the 140mm version should work well for the 600/4. B&H sells them (as special order items, with 2-4 week delivery; Google shows other US suppliers with stock on hand). I'll need to decide whether I'm going to take the 600/4, or use the RF 100-300/2.8 with a TC.

My older daughter is very excited about the eclipse, and at her request we are planning to drive up to New Hampshire for the event.

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Glad this is useful. I take it you're planning to use the R3? I'm curious how the eclipse will appear in the electronic viewfinder, compared to the optical viewfinder of my 1DXIII. There are incredible nuances in the corona, and a huge dynamic range, that the EVF might not be able to display. You'll get the same photos (if not better) with the R3, but for the personal viewing experience, I'm wondering if it will match the optical view.

Also - New Hampshire has a low probability of clear skies on eclipse day, unfortunately (cloud cover > 70% typical). Locations farther south are better. https://eclipsophile.com/wp-content/...ntre-cloud.png

For the annular on 10/14 will be along the line in Nevada or Utah in the BAM 'boondocking' and will be using my 1200 russian mirror w a solar film fits nicely in my friction fit clear filter.

If anyone is interested Vegas or St. George Utah are not far and could pick anyone up at that airport(s). Will have the Jeep so travel is fairly easy and nearly anywhere we would like to go.

Thanks, Jonathan. Personal viewing will be through (filtered) binoculars. Good point on the cloud cover, though with school we won't be able to travel more than a few hours' drive so there's not much difference between New York and Vermont. Given the timing, we'll be able to make a call early in the morning and drive west or north depending on the proximate forecast. Unless it's all clouds in which case we'll stay home and watch online.

There's a great little natural history museum in northern Vermont that has a planetarium (Fairbanks Museum in St. Johnsbury), that we've visited several times. It's just inside the totality (~90 s worth), we were considering using that as a base for a short drive north if we go that direction. Burlington, VT is right in the middle, but will be very crowded.

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Originally Posted by Jonathan Huyer

Glad this is useful. I take it you're planning to use the R3? I'm curious how the eclipse will appear in the electronic viewfinder, compared to the optical viewfinder of my 1DXIII. There are incredible nuances in the corona, and a huge dynamic range, that the EVF might not be able to display. You'll get the same photos (if not better) with the R3, but for the personal viewing experience, I'm wondering if it will match the optical view.

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Wouldn't it be the same as using live view. I did live view on all the shots with the 500mm on the last one.
I would think with the high frame rate of the R3 you will can have quite a few shots through total. Or just one or so at 196 fps.

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Originally Posted by Jonathan Huyer

Also - New Hampshire has a low probability of clear skies on eclipse day, unfortunately (cloud cover > 70% typical). Locations farther south are better. https://eclipsophile.com/wp-content/...ntre-cloud.png

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Weathermen fail at predicting the weather tomorrow, counting on patterns is at best unreliable. Last year we had one of the hottest summers on record and this year record rainfall in the driest month of the year.

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Originally Posted by neuroanatomist

Thanks, Jonathan. Personal viewing will be through (filtered) binoculars.

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Speaking of which, if any one reads this for pointers, buy a filter for a good set of binoculars like Canons IS binoculars.
I had both filters and a pair that was made to view the sun. The special pair was good for the kids to play with while they ate popsicles.

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Originally Posted by HDNitehawk

Speaking of which, if any one reads this for pointers, buy a filter for a good set of binoculars like Canons IS binoculars.

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That was my plan. The 10x42 IS takes 52mm threaded filters.

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Originally Posted by neuroanatomist

That was my plan. The 10x42 IS takes 52mm threaded filters.

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I ordered binocular solar filters from the same company I got the camera lens filter, because I like the idea of an unthreaded filter you can slip off easily. During the total phase, you will want to use the binoculars to see the intricate details of the corona, prominences, and all that good stuff. So having a filter you can pull off quickly would be an advantage. Or, have a second pair of binoculars handy (unfiltered) that you can grab quickly.

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Originally Posted by HDNitehawk

Wouldn't it be the same as using live view. I did live view on all the shots with the 500mm on the last one.
I would think with the high frame rate of the R3 you will can have quite a few shots through total. Or just one or so at 196 fps.

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What I'm wondering specifically, is how the image would look in the viewfinder for a mirrorless camera, if you compared it to a DSLR side by side. The EVF is giving a 'TV screen' view of the scene, whereas the DSLR is showing you the real McCoy. For most scenes they look pretty similar, but a solar eclipse is a very unique situation with incredible dynamic range. I expect that the actual photos each camera will produce will be quite similar, but for anyone who has taken a picture of a solar eclipse already knows, the picture doesn't come anywhere near to what it actually looks like through the optical viewfinder (or binoculars). So my question is whether the EVF will have similar limitations, such that you're perhaps better off viewing the eclipse through binoculars while taking photos with the mirrorless camera, just so you don't miss out on the full experience.

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Originally Posted by Jonathan Huyer

What I'm wondering specifically, is how the image would look in the viewfinder for a mirrorless camera, if you compared it to a DSLR side by side. The EVF is giving a 'TV screen' view of the scene, whereas the DSLR is showing you the real McCoy. For most scenes they look pretty similar, but a solar eclipse is a very unique situation with incredible dynamic range. I expect that the actual photos each camera will produce will be quite similar, but for anyone who has taken a picture of a solar eclipse already knows, the picture doesn't come anywhere near to what it actually looks like through the optical viewfinder (or binoculars). So my question is whether the EVF will have similar limitations, such that you're perhaps better off viewing the eclipse through binoculars while taking photos with the mirrorless camera, just so you don't miss out on the full experience.

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I think the big difference would be the quick adjustment you have to make to get the picture exposure. Initially all you will see is a black screen in either and be frantically changing the shutter speed as you pull the cap off. A DSLR you see what you see, but I think you know as well that what you see through the 1D viewfinder is better than what you see in a lesser body. So you will loose site of the sun if you are doing it hand held. What you describe would be great, but the sun moves quickly out of view with the 500 or 600mm. You are talking adjusting, tracking and looking through the binoculars in a period of time less than what it took me to type this.

What would be good to have is a mount for the tripod that can track the sun, have a good idea of the required shutter speed so you can quickly go to it.

Yes for sure, with regards to picture exposure, you would need to be ready in advance of the total phase. For the 2017 eclipse, I didn't bother taking any photos in the partial phase. I simply used the lens with solar filter as a means to view the eclipse. I had the camera preset for the total phase, which involved using exposure bracketing. I set up the bracketing for 7 shots with 1-stop gap, using a base ISO, aperture, and shutter speed that I got from reference material. I had the drive mode on high speed, and used a remote cable to actuate the shutter. So all I would have to do is make sure the image was still in the middle of the frame, and hold the button down while the 7 shots were taken each time. The bracketing was enough to ensure that I got the prominences (at the low end of the exposure) to the intricate details of the corona (at the high end of the exposure).

I think a potential disadvantage to using a mirrorless camera for the eclipse is that in order to view the partial phase, you would need to have the exposure set for that particular condition. Then you would have to switch rapidly to the new settings for the total phase. With the DSLR, it doesn't matter of course what your settings are --- the viewfinder image will be the same. So if you're like me and don't care for photos of the partial phase, then you can do it as I described. Or, just take photos of the partial phase after totality, so you aren't in a panic to switch.

As examples of what I got with bracketing:

1/30 sec @ f/5.6, ISO 200
https://photos.smugmug.com/photos/i-...qFSJSNn-XL.jpg


1/1000 sec @ f/5.6, ISO 200
https://photos.smugmug.com/photos/i-...28wv2Jn-XL.jpg


Note that with an optical viewfinder, you'll see the prominences at the same time that you see the incredible detail in the corona, but only with your eye. The camera can't capture both at the same time, due to the huge dynamic range between them. With a mirrorless camera, you will need to physically change the settings to see the prominences or the full corona, because what you see is what you get.

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Originally Posted by Jonathan Huyer

What I'm wondering specifically, is how the image would look in the viewfinder for a mirrorless camera, if you compared it to a DSLR side by side. The EVF is giving a 'TV screen' view of the scene, whereas the DSLR is showing you the real McCoy. For most scenes they look pretty similar, but a solar eclipse is a very unique situation with incredible dynamic range. I expect that the actual photos each camera will produce will be quite similar, but for anyone who has taken a picture of a solar eclipse already knows, the picture doesn't come anywhere near to what it actually looks like through the optical viewfinder (or binoculars). So my question is whether the EVF will have similar limitations, such that you're perhaps better off viewing the eclipse through binoculars while taking photos with the mirrorless camera, just so you don't miss out on the full experience.

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Yes, the EVF will have the same limitations as the captured images. Probably the "OVF Simulation' mode of the R3 will be better in that regard, but it's still not going to match an OVF in that situation. Agree that viewing with binoculars would be better, but I think that's generally true anyway for both solar and lunar eclipses.

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Originally Posted by Jonathan Huyer

As examples of what I got with bracketing:
1/30 sec @ f/5.6, ISO 200
1/1000 sec @ f/5.6, ISO 200

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With just the shutter speed changing, that's pretty easy to adjust rapidly on the fly. That's a 5-stop difference, so it's within the range of AEB and since the R3 brackets at 30 fps with full 14-bit RAW honestly it's probably easiest just to take bracketed exposures and either combine them or delete the unwanted ones.

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Originally Posted by neuroanatomist

With just the shutter speed changing, that's pretty easy to adjust rapidly on the fly. That's a 5-stop difference, so it's within the range of AEB and since the R3 brackets at 30 fps with full 14-bit RAW honestly it's probably easiest just to take bracketed exposures and either combine them or delete the unwanted ones.

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Yes good point --- it's pretty easy and quick to make the changes. I'd still suggest rehearsing the moves ahead of time, because the event is so utterly phenomenal that you can temporarily lose your mind while being in the midst of it. If you're already an eclipse veteran then you'll probably be a bit more level headed, but even though the 2017 eclipse was my third, I was still massively overwhelmed. Maybe it's just me, but I find these events so paralyzing that I almost forget to breathe! I'm sure looking forward to next April, and I wish everyone clear skies wherever you may be.

Jonathon, are going to try tobhit the annular in October? I will be in Vegas on the 12th will be staying over for it.

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Originally Posted by Busted Knuckles

Jonathon, are going to try tobhit the annular in October? I will be in Vegas on the 12th will be staying over for it.

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Regrets, I'm going to miss it. For me, an annular eclipse is pretty cool, sort of like a lunar eclipse, but not "exciting" enough to warrant a special trip. I did see one in San Diego about 30 years ago, which worked out well because I had family there at the time. It happened right at sunset, which was super cool because we could see the eclipsed sun setting into the ocean. I hope it works out for you!

Thanks again for the tips, Jonathan. I just ordered the ASTF 140 for my 600/4 II, the ASTF 120 that will fit either my 100-300/2.8 (600/5.6 in this scenario) or my daughter's 5" reflector telescope, and a pair of ASBF 50's for my Canon 10x42L's. I also ordered a pair of screw-in aluminum hoods for the binos, the Canon design for the two pairs I have (10x42L and 10x30 IS) is such that there's very little objective lens housing protrusion on which to push-mount the solar filters compared to 'typical' designs like the Nikons on the left.

Attachment 3035

This is just a friendly reminder to the forum....the eclipse is about 3 months out (April 8, 2024). If you want a solar filter, you likely want to order yours soon. As I recall in 2017, you could get the eyeglasses ~2 weeks before, but legit photography solar filters ran out early, and even a quick review of solar telescopes, those are listed as backordered in a number of outlets.

BTW, I have recently discovered the app "astrospheric" which has a layer on their map for the 2024 eclipse...some great information on the path, % eclipse by location, and duration.

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Originally Posted by neuroanatomist

Thanks again for the tips, Jonathan. I just ordered the ASTF 140 for my 600/4 II, the ASTF 120 that will fit either my 100-300/2.8 (600/5.6 in this scenario) or my daughter's 5" reflector telescope, and a pair of ASBF 50's for my Canon 10x42L's. I also ordered a pair of screw-in aluminum hoods for the binos, the Canon design for the two pairs I have (10x42L and 10x30 IS) is such that there's very little objective lens housing protrusion on which to push-mount the solar filters compared to 'typical' designs like the Nikons on the left.

Attachment 3035

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Can you let me know which lens hoods you got for the Canon 10x42? I have the same binos and agree that it's tough to attach the filters to it. I tried the size 50 first and it was too small. Then I went with a pair of size 70, and could not get them both on at the same time. So I decided on a hybrid solution which I think is going to work really well: I will attach a filter to one lens only, and add a few elastics to make sure it's on firmly. Then I can put the lens cap on the other lens, and view the partial phase through the filtered lens only. When the eclipse is total, I can flip off the lens cap quickly and switch to that side (unfiltered). That will be faster and simpler than trying to remove two filters from the binos. But I'm keen to hear more about your solution.

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Originally Posted by Jonathan Huyer

Can you let me know which lens hoods you got for the Canon 10x42? I have the same binos and agree that it's tough to attach the filters to it. I tried the size 50 first and it was too small. Then I went with a pair of size 70, and could not get them both on at the same time. So I decided on a hybrid solution which I think is going to work really well: I will attach a filter to one lens only, and add a few elastics to make sure it's on firmly. Then I can put the lens cap on the other lens, and view the partial phase through the filtered lens only. When the eclipse is total, I can flip off the lens cap quickly and switch to that side (unfiltered). That will be faster and simpler than trying to remove two filters from the binos. But I'm keen to hear more about your solution.

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Hey Jonathan.

I guess the Canon 10x42 set of binos is popular. I have a pair as well. In 2017, my sister called watching the eclipse (non-totality) through them her favorite part.

They take 52 mm filters.

I have ordered a set of these from Thousand Oaks:

Threaded Camera Filters – Thousand Oaks Optical

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Originally Posted by Jonathan Huyer

Can you let me know which lens hoods you got for the Canon 10x42? I have the same binos and agree that it's tough to attach the filters to it. I tried the size 50 first and it was too small. Then I went with a pair of size 70, and could not get them both on at the same time.

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Apologies, I missed this question. I use the Baader ASBF 50. Given your comments above about needing to quickly remove the filters during the totality, I wanted to avoid threaded filters. Looking at the binos, I assumed the Baader filters would not have anything to grab onto, so I took advantage of the threading and ordered a pair of these 52mm threaded hoods. The setup with the ASBF 50s and the hoods works great, and the hoods are short enough they don't vignette at all.

Brant and Neuro -- thanks for the great info. The screw-on filter from Thousand Oaks is a good option for sure, although it might be better to just use one of them. Then you could view the eclipse through the filtered lens during the partial phase while keeping a lens cap firmly on the unfiltered lens. Then when totality hits, you can pop the lens cap off the unfiltered side and gawk away safely until totality ends. Or I suppose you could carry two pairs of binoculars, one with filters and one without! Either way, I found viewing totality through unfiltered binoculars to be the greatest sight in nature I have ever seen. You get incredible details, from the prominences to the exquisite filaments in the corona. It's definitely worth having some magnification to enjoy that to the fullest.

I'll go with the lens hood that Neuro suggests, since I already have the Baader filter.

Thanks again!

Couple of items: Just got the 5d3 back from lifepixel - both IR and UV cut have been removed. Suggestions for testing are appreciated.

For the solar eclipse I am planning on using the same system I used for the annular eclipse - filter holder w/ solar film. For exposure 'jumps' from from pre to totality and back, planning on using the Custom mode to preset the jump about 10 stops.

Would love to figure out something for the full spectrum 5d3 - have the tamzooka which has a 95 mm thread or the 70-200 with a 2x for 400mm reach and a 77 mm thread. I know a 77mm H-alpha would be pretty spending at these diameters...... IF you could find one and IF it wouldn't result in the sensor being fried. Any thoughts, suggestions, would be appreciated.

Hi Mike...

I know we've chatted about this. I do worry that the Ha filters you are talking about are for astro, not solar. Ha filters for astro fall into "narrow band" imaging as light for astro is typically coming from reactions involving oxygen, hydrogen (Ha), and sulfur. Thus, if you look for a "narrow" band around those emissions, you can pull out different and get more detail of nebula, etc.

But the real purpose of narrow band imaging is to avoid issues from light pollution. By focusing on wavelengths from space, you minimize the impacts of light emanating here on the planet (which is different wavelenghts) and bouncing around our atmosphere, interfering with the final image. So, the intent of narrowband imaging is to clean up the light hitting a sensor and to focus it on what is coming from Space.

But, "narrow band" for astro is typically 10-30 nm. When I've looked at Ha filters for solar imaging, they are trying to tightly focus on the peak of hydrogen alpha, 656.3 nm. Single stack are typically getting you a 0.7 nm range around the peak, and then double stack are usually less than 0.5 nm. So, solar imagers are really trying to be ~656.0 nm to ~656.5 nm, or tighter.

While I do not know this for sure, my concern is that 10-30 nm is not narrow enough and will let too much other light through, thus washing out Ha. So, it would be a red, detail-less image. I could be wrong. I know this as I was looking into the exact same thing but have so far opted to not go for it.

BTW, why Ha? This stuff facinates me, different light (and gravity for that matter) come from different layers of the sun. The different layers being at different temperatures, pressures, and even compositions support different reactions. At the very surface, the chromosphere which is hotter (~20,000C), is a reaction where the electron in hydrogen changes state with the temperature causing it to rise (to n=3), and as it falls (to n=2) it releases 656.3 nm light. Electron state change from n=3 to n=2 is called an "alpha"...as this is coming from a hydrogen atom, you get "hydrogen alpha" light.

White light mostly comes from the photosphere, which is just below the chromosphere. But the chromosphere being the surface, to see what is happening on the surface, you look for Ha bandwidth.

Getty back to my concern, if you do not get narrow enough around 656.3 nm, other light from the photosphere may still drown out the Ha light, thus the details of the chromosphere that we all want to see.

Like I mentioned, I've looked into it. I've decided to save my money at this point, but if I was to do it, I was leaning toward getting a Lunt 50 mm single stack dedicated solar telescope. The primary reason being, turns out, to get good photos of Ha, most solar photographers are using monochromatic cameras as our darn Bayer arrays actually are not tuned to Ha light. So, to do it well, you likely need both a dedicated telescope and a dedicated camera. That is a bridge too far for me.

So, for now, I am still thinking of just using white light filters with my camera lenses.

Thanks,
Brant

I am going to at least double stack.

The 1st filter will be the solar film - 1st attempt - with the Ha after it. 2nd attempt will be the 10x nd filter with the HA after it. I will absolutely test the the 2nd attempt w/ a non camera rig - basically a large magnifying glass projecting to a board of some sort with temps being measured from ambient. Much of a step up in temp is a no go.

The higher reputation youtube folks pointed out that about 40% of the light from the sun - getting through the atmosphere/ozone layer - is IR we can't see, 50% visible and 10% UV. Excluding IR/Visible make UV exposure values drop.

I totally get that the visible/uv cut filters likley allow a very broad IR light stream in which might be too diffused in its origin to create any texture in the sun surface - we will find out when the filters arrive.

Getting close now. We're fortunate here, the weather forecast for northern Vermont is clear and sunny (though this is New England where they say, "If you don't like the weather, wait 5 minutes,"). Looks like much of the rest of the US path has less of a chance of clear weather.

I'm planning to use the R3 with the 600/4 II + 1.4xIII with the Baader ASTF 140 filter, mounted on the RRS TVC-33 with a side gimbal. We have eclipse glasses for the whole family, the Canon 10x42L binos with Baader ASBF 50 filters, and a couple of Nocs Provisions 8x32 monoculars with eclipse filters that the kids can look through and/or use for digiscoping with their phones.

My daughter has decided not to bring her telescope, so I have a 'spare' Baader ASTF 120 filter, thinking about what (if anything) to do with that. It will fit the hood of the 100-300/2.8, so I could set that up with the 2x TC on my travel tripod (RRS TQC-14)...but honestly one camera is probably sufficient, and I was planning to use the travel tripod for the 10x42L binoculars (I have a little Hejnar plate on it that used to go on my M/M2 but I don't use on the M6/M6II since the dedicated Acratech M5/M6 plates fit better). I could mount it in front of a camcorder and video the eclipse in addition to taking photos.

Mike, any results from playing with your full spectrum camera? I have a full spectrum M6 (along with a UV bandpass and several IR longpass filters). Given the discussion above, I could clamp the ASTF 120 to a tripod leg (i.e. held in a Justin clamp connected to an RRS multiclamp on the leg) and shoot through it with the M6 handheld (or tripod-mounted). I haven't had a chance to play with that with the sun, and we may not have sun here until Monday anyway.

Certainly, I plan on just viewing the eclipse with binoculars and with eyes using regular eclipse glasses (and not, during the totality) – I don't want to spend the whole time looking through/at the camera.

Brant, are you heading north? We're likely going to Newton, VT.

Hey Neuro…I am down just outside of Austin Texas in a house I rented under the path of totality.

Honestly, the forecast isn’t looking great. As you mentioned, I may have left the area with the best weather to come here. But, I have turned this into a mini family vacation so we decided to take the chance.

I decided to go with the RF 200-800 with Baader film filter. I also have multiple binos (supplying for the extended family) with various daystar or thousand oak filters.

Hoping for the best! Good luck everyone!

Have to get the raw files onto the computer and fiddle w/ the red channel - the IR is clearly very hot compared to visible light. The image in the viewfinder was substantively different than the screen/sensor. I don't know if the dial back on the red and push of the blue/green has any value. Will find out soon

Camera JPG at https://www.flickr.com/photos/77760916@N05/

Nice, Mike!

I decided to KISS, just brought the R3, 600/4 and 1.4x. Better to enjoy the event with family than juggling two cameras, filters, etc. I set the camera to a 7-shot bracket covering a 12-stop range, and triggering with the BR-E1 remote fires the whole bracket with one press, which meant I could enjoy the experience with just an occasional repositioning of the gimbal (and removing/replacing the solar filter for the totality. RAWs are still in the camera, will post pics once I get them processed.

The answer is that the IR blows out everything else. There is some enhancement not enough to post yet.