How to meter/expose for solar eclipse?

[cirwin2010]

I hope to capture the 2024 north American solar eclipse and I'm working on gathering what information I can in advanced. I want my final output to be a large silver gelatin print so I'll obviously be shooting with black and white film. Obviously proper protective filters and eye protection will be used.

I just don't know how to meter and expose for totality and the moments leading up to and following it. With digital it would be easy enough to bracket shots, but I would like to know if bracketing can be avoided.

Does anyone have any information or references that may help?

 

[ic-racer]

It will be pretty dark, I’m going to use the cameras ttl meter and a tripod. Maybe bracket some to bring out the moon.

I watched some YouTube videos to get an idea of the duration for totality.

I have never seen an eclipse. Last two overhead were 1430 and 1820.

 

[Paul Howell]

When I shot the last big eclipse I used a good grade filter made for shooting solar eclipses, I shot digital, used a 400mm lens, tripod and just used the TTL metering all my shots were spot on. What camera and lens do have and what film are you thinking about. If it was me I would go with Tmax 400 at 400. One advantage of shooting digital was I kept the camera in auto ISO mode.

 

[DWThomas]

It depends a lot on what you want to photograph. For the direct moon and sun coincidence you can preset exposure by putting a suitable (and substantial!) neutral density filter on the lens and aiming it at the full sun. That will cover you until you get within totality. I used all manual settings in 2017. It's even recommended to tape the focus ring on the lens, as autofocus will get lost somewhere along the way, and working at some weird upward view in the dark is tedious enough! I know I lifted the solar filter off during the 2 minutes or so of totality, but don't recall any exposure adjustment. Probably even spot metering would be extremely difficult to produce anything meaningful, and somewhat depending on where you're shooting from, the totality phase is quite short just a minute or three.

Another problem I found was that at high magnification there is surprisingly rapid movement and it was extremely difficult to figure out where the frame was when trying to recenter the image. Probably a geared head with one axis set to parallel the path would be cool -- or a full-blown clock drive as used for general astronomy. But for using once every decade or two, that's a lot of overhead.

If you wanted to include a broader view and see some peripheral detail, that might suggest a bracket, bracket, bracket approach. But consider that at near totality you are looking at a huge scene brightness ratio situation.

(See -- I did it once and now I'm an expert! )

Edit: In the gallery page at the above link, the first two thumbnails open sub-galleries with (manually timed) interval shots.

 

[resummerfield]

The Mr. Eclipse site ( http://www.mreclipse.com/MrEclipse.html#Sun ) has some interesting info.

 

[TJones]

Your exposure settings will depend on what you want to capture. To preserve the solar prominences (those little loops that extend out from the surface), you'll be in the range of ISO 100, f/16, 1/250. They quickly get washed out by longer exposures. If you want a photo of the corona and maybe a couple of stars, you can open up the aperture a couple of stops, and then take multiple shots with successively longer shutter speeds.

I also pre-focus before totality, switch to manual so it won't start hunting, and tape down the focus ring.

Totality is going to be relatively long for this one if you get close to the center of the track, so you'll have plenty of time for quite a few exposures, unless you're shooting large format.

 

[Paul Howell]

I had forgotten that I also turned the AF off and taped the focus in place. I also used a remote to fire the shutter.

 

[Sirius Glass]

Do not look directly through the view finder except at totality.

 

[TJones]

I had forgotten that I also turned the AF off and taped the focus in place. I also used a remote to fire the shutter.

I also used the remote; thanks for the reminder.

 

[DWThomas]

Do not look directly through the view finder except at totality.

I say you can do so if you are looking thru an SLR with the solar filter on but certainly not without a filter. Likely your focal plane shutter wants a filter too!

Heh, back in 2017 every order I placed with B&H leading up to the eclipse was sent with a free packet of cardboard framed viewing glasses. I gave a few to folks at the Illinois park who got there after the park people ran out. The cardboard jobbies I bought to slide over my lenses were inexpensive and did the job; I added some weatherstrip foam inside the circumference to help keep them in place. The cheapies have a yellow cast which can be seen in the digi-shots I linked to. I'm considering buying one of the metal framed "real" filters for 2024, but am not sure if they are neutral color-wise. Likely as soon as I purchase any better gear I'll either croak or it will be cloudy and raining.