Solar Filter for DSLR Camera

[Weekes]

Sorry if this is a really newb question or there's a guide in a really obvious spot that I've overlooked :rofl:
The situation is basically this: I have a Canon 550D and I want to get some photographs of the sun, but I'm not sure what to look for in ways of protection? I have read that you can make your own filter and save a buttload of cash. How reliable is doing such a thing compared to buying a "proper" one?
If anyone can just nudge me in the right direction I would greatly appreciate it! Thanks!

[pluto]

I made a solar filter to use on a Canon 70-200mm for the 2012 TSE.
I bought a really cheap 58mm uv filter from ebay, then cut up a spare pair of eclipse glasses (available from the IIS store I believe) and some cardboard and taped it to the filter. Total about $5 I think.
Should make more sense in the pictures:

[Weekes]

That is incredibly nifty! but with cardboard over the lens does it affect images? I'm thinking of doing that on my 55-250mm?

[pw]

You'd be better to buy a sheet of the Baader solar film and make a filter from that.
It's around $35 for an A4 sheet and comes with instructions on how to make a good filter. I used it with my 300/2.8 and 2X teleconverter to shoot this pic. https://www.flickr.com/photos/pw-pix/12377076214
https://www.flickr.com/photos/pw-pix/12377061134

[pluto]

Well at 200mm or 250mm the sun is pretty small in frame and you're really only using the centre of the lens so the cardboard surround is just to make sure no sunlight enters the lens.

[Merlin66]

Baader solar film is the way to go....
Which telelenses will you use?

[04Stefan07]

I did the exact same thing!

[Weekes]

Canon EFS 55-250

[JB80]

I used a pringles container to cover my 75-300mm zoom lens. It was a loose fit but you can easily tape it down and it's not an issue at all except in high wind.
Just cut the tube down and then you cut out the inner part of the lid and from there you basically just clip a small sheet of solar film to the container like you would when you normally put the lid on.

I can't find the photo of it atm, if I do I'll post it.

[julianh72]

That method is fine, but a word of warning:
You want to be 110% sure that there can be absolutely no light leakage between the cardboard blank and the metal filter ring, and also no chance of light leaking between the solar filter film and the cardboard blank. Even a very small amount of unfiltered sunlight could do permanent damage to your camera - or your eye! I'm a little bit concerned about the possibility of a fine gap between the cardboard blank and the metal filter ring in your photo - as long as the metal ring has a "landing" of a mm or two width to land the cardboard blank on, OK, but if not, you might want to consider fully sealing the perimeter with 100% opaque masking tape or similar.

I bought some solar film on eBay, and have successfully made solar filters for everything from my camera's longest telephoto lens, to a 76 mm reflector, 90 mm refractor, 130 mm reflector, and 200 mm SCT, using this method:
http://www.baader-planetarium.com/sofifolie/bauanleitung_e.htm

[Merlin66]

Matt,
the size of the solar disk is close to 1/100 the focal length - the image with the 250mm will only be 2.4mm diameter.....

[pluto]

I was very careful to make sure there was no gap (it snapped into the internal thread so it was very secure and was a snug fit) and I never looked through the viewfinder, only at the screen, so the worst that could happen was the camera would be damaged.
I made it that way as I wanted a filter that could be removed quickly and precisely during totality and then be replaced as totality ended.

[julianh72]

My comments were aimed more at anyone who might copy your method than they were at yourself! :thumbsup:


I was thinking that you (or someone copying your method) could still achieve that using multiple short pieces of masking tape all the way around the perimeter of the filter frame, leaving the thread clear to allow installation / removal without running any risk of light leakage due to handling etc.

I got some reasonable shots of the transit of Venus in June 2012, and the Cairns solar eclipse in November 2012 (in the few minutes when the sun wasn't obscured by clouds :( !) using a Variable ND400 Filter (i.e. a coupled pair of polarising filters) on my 300 mm telephoto on my Canon DLSR (500 mm / 35 mm equivalent), but I hesitate to recommend this to others because polarised filters need to be very good quality to achieve the block-out (when crossed) which is necessary for safe solar viewing - and you need to be VERY careful not to accidentally rotate the front element during viewing. The solar film method is generally much safer.

[pluto]

Agreed :thumbsup:

I certainly wouldn't recommend it but this was my setup for the transit of Venus, again it was half a pair of solar viewing glasses taped (securely) to some black card with a hole cut in it. I didn't go anywhere near the viewfinder with this setup, in fact I used DSLR controller on my phone so I could focus without putting my head anywhere near it!

[Weekes]

Thanks all for the input, I've learnt a tonne from this post :lol:
I think I'll start with the first suggestion from pluto because of the simplicity and cheapness before moving onto a more lasting filter when and if I decide to upgrade my lens or add a teleconverter.
Thank you all for sharing your little inventions though! They're great

[pluto]

Ok but please be REALLY careful!

[Weekes]

Of course, I will NOT being going anywhere near the viewfinder at all. Screen all the way :cool2: