Imaging the eclipse?

[Thalestris24]

Hi all

Any hints and tips how best to image the eclipse on the 20th? I have the solar film but not sure about exposure times. I'll probably use my modded 1100d and either the 130pds or ST80. Might there be any advantage to using any standard nb filters as well as white light? I appreciate a 7nm Halpha isn't going to show the details a solar Ha would.

This is probably all academic as it's certain to be cloudy here anyway...

Thanks

Louise

[Montana]

I've no idea but I need to make my WL filter from my Baader film and have a good practice on the Sun well before the event to get the settings right. If I ever get to see the Sun on a weekend I would also be interested to know which ISO, I'm guessing 100 will be best.

Alexandra

[JB80]

Hi Louise, If it was me I would go for the 130P-DS, however I would practice first with both and see if one gives a more pleasing result. I know plenty would prefer a frac over a newt so if you are making a filter I'd use the one you think you would use the most.

I normally use a OIII filter with my white light and reports I have read have shown that a 7nm Ha works really well to bring out contrast however seeing as for you guys the Sun will be mostly covered then there is probably no need for one getting in the way.

Yepppers, ISO 100 is definitely where I would start, I can't give the exact exposure as every scope will be different but it will be on the quick end of things. Again I'd get in before the fact and work this out so you are ready come eclipse.

I'm sure you will get a clear spell or two Alexandra, my fingers are crossed for you.

[Thalestris24]

Ok, thanks. I was wondering how to adjust exposure near maximum eclipse to get the best result or should I maybe use auto? Thinking about it, I don't suppose many others have experience of imaging eclipses!

Cheers

Louise

[JB80]

I have imaged an eclipse but it was only partial and there was no need to adjust the exposure from a normal full disc shot so if I'm honest I don't really know if you will need to adjust it because so much more of the sun will be covered but if you find the picture is getting too dim then I'd manually increase it.

Don't use auto as there is every chance that will over expose things. What I normally do is set my dial on the camera to M, turn all the auto things off in settings like auto ISO and noise reduction and I take it from there.

Even just a little bit of haze or cloud can dramatically change the exposure you need so you may need to keep on top of that.

[Thalestris24]

There's a 90% chance it will be cloudy if not raining! That's Glasgow for you...

[JB80]

Oooh, I didn't see that. I hope it isn't, I want everybody to have a nice sunny morning.

[DrRobin]

Hi,

I went to France for the 1999 eclipse, it came in cloudy, saw it up to just before the diamond ring and took a few images with a Pentax film camera, must find them some day.

This year I am going to do a public display with white light and Ha, using my webcams as normal. Here we are going to get about 92% totality, you will get slightly more, but I don't suppose exposure times will be much different to normal full disc. For near totality I would have thought white light would look just as good as Ha.

I know the weather might not play ball, but think on the bright side, it could be great and you are in a better position than many. Anyway I have booked my day off work, a rare occurrence for me, so hope we all get at lest a brief view.

Robin

[Thalestris24]

Thanks Robin

I'll try to think positive! Fingers crossed and hope your public display goes well!

Louise

[JamesF]

For a full solar disc with Baader film and my 450D on the 127 Mak I use something like 1/1000th @ ISO100, but I think it may take a bit of experimentation to find out what works for you.  I'd agree with the choice of 130PDS.  If you have a way to fit a decent 2x barlow in there as well then that would give you a very nice focal length for the size of the 1100D sensor.

Getting some practice in beforehand is a must though.  Even if it's cloudy you may be able to learn more about what works and what doesn't as long as the Sun manages to scrape through the cloud somehow.

James

[JamesF]

Oh, and I'm sure you realise this, but if you're not sure, opt to underexpose rather than overexpose.  You can always stretch the data you have.  You can't "unclip" the overexposed stuff.

James

[Thalestris24]

Hi James

I've had a go at solar before last summer though not very successfully and put my solar imaging ambitions to one side. I could get exposure ok but could never get sharp focus. I did ask for advice on here at the time. I thought I'd followed the Baader instructions ok. However, I recently found there was actually still a thin film of clear plastic on the solar film which was probably why I couldn't get the sharpness! D'oh! Nobody here suggested that might have been the problem... Anyway, I'll have to knock something up for the 130pds. At leas I'm aware of the plastic now! Hope I get a chance to practice

Louise