1st Light With The Canon 40mm f/2.8 STM Pancake Lens

[StuartJPP]

Last weekend I had the opportunity to get out with the above lens. The one thing that I am not too sure about is that it is a focus by wire design...so you can't focus it without it being attached to a Canon body or at least without some method of providing power to it. Unlike most lenses it doesn't seem to focus past infinity, there isn't a hard stop but I am used to lenses focusing past infinity and you usually have to tweak it back a notch. I didn't connect the camera to APT, which I probably should have but seeing conditions were not perfect as there was a lot of moisture in the air at the time.

Other than astro work, it is a nice sized lens to complement the 500mm in my backpack, takes up very little space and is very light.

So not a great test due to poor seeing conditions, but overall not too bad for the price. The edges are cropped since as we all know that imaging wide open is not the best on these wide angle lenses. A front aperture mask might be a bit tricky with this lens...

Modified Canon 1100D
Canon EF-40mm f/2.8 STM Pancake Lens @ f/2.8
AstroTrac TT320X mount
ISO400
12x 240 second subs

10 November 2013

Thanks for looking.

M45 - Pleiades and NGC1499 - California Nebula by StuartJPP, on Flickr

[Alien 13]

WOW nice.

[Gina]

Very good

[iksose7]

An excellent lens for the money! Proven with this image. I do know one other person that uses this lens and also produces great images. Its one i want in my kit bag at some point, near perfect for constellation work.

[ollypenrice]

Wide!!!

Olly

[davew]

Very impressive.

Nice stars and quite efficient on the red stuff. What I particularly like though is the dust detail. Many images show the thick stuff but you've captured the fine swathes as well. Nicely processed.

There are a few lenses knocking about that have to be powered as you'll already know. That's going to make things difficult as time goes by for those of us with CCD cameras. I've seen one attempt at powering on a CCD that extended the connections and wires to a DSLR body mounted at the side. Complicated and fraught though successful!

I think aperture masks can be a fine balance too. Make them small enough to sort a wide field lens and the FR goes too high. Does the lens correction feature on the Canon raw converter help ?

Dave.

[andyo]

That's a very nice wide shot of these two objects and the dark stuff really adds to it

[laser_jock99]

Nice widefield image.

[Coco]

Excellent wide field, you have captured lots of interest.. very nice

[StuartJPP]

Thanks for commenting everyone...

Dave, regarding lens correction...I don't know I just stack the RAW files. It may be able to correct distortions like barrel/pincushion but I wouldn't have thought it could correct coma.

[RikM]

That is a splendid image. Did you have to run a dew band or shield or something?

[davew]

Thanks for commenting everyone...

Dave, regarding lens correction...I don't know I just stack the RAW files. It may be able to correct distortions like barrel/pincushion but I wouldn't have thought it could correct coma.

I was thinking along these lines ( See photos of one of four comma ridden corners ) Semi fixed in PS. Unfortunately it is global and therefor effects all the image.

If it won't work, then it won't work. Worth posing the question.

Dave.

[StuartJPP]

If it won't work, then it won't work. Worth posing the question.

Certainly is worth posting the question and when I get time I will try to see if I can get something more out of it. However bright stars in the corners are pretty dire (probably not helped by the seeing conditions on the night). Even though what you have done affects the whole image, you can always use a mask to only affect the corners. I think StarTools has a coma correction filter, might give it a try.

That is a splendid image. Did you have to run a dew band or shield or something?

Thanks, nope no dew band but I was using a lens hood (an ES-62 not the crazy one specifically designed for this lens). By the end of the night the lens element was clear but the hood had a tiny puddle of water in it