Page 1 of 1
500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 1:54 am
by David Kilpatrick
Very careful focusing using maximum live view magnification, 10s delay timer, electronic first curtain. Very slightly reduced from 1153 pixel square clip of A77 frame from raw. Don't really think it is sharp enough.

- 50mma77.jpg (245.17 KiB) Viewed 3310 times
Really need an Apo 800 or 1000mm or longer for this
David
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 2:32 am
by InTheSky
I think It was sharper with the A700 and the 500mm REFLEX AF as I can remember.
I was expecting more from the A77. But probably the lens is in fault ?
Frank
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 4:32 am
by Greg Beetham
Well I think it’s magnificent at such big crop posted at such a big size, it would look a lot better at a smaller post size I reckon. The full moon is hard too get contrast out of from my limited experience at dabbling with the odd photo, I was thinking of experimenting with exposing more for those bright reflective craters some day like Tycho (lower right with the radial spokes), Aristarchus and Copernicus maybe as well are very bright, I don’t think you could actually expose for Aristarchus as it’s too bright I think, there is something odd going on with that crater actually, it’s hard to believe all that brightness is just reflected sunlight.
Greg
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 6:42 am
by Dr. Harout
David, did you turn off the SSS? I believe you didn't and I don't think the a77 is "smart" enough to disengage SSS while on timer.
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 1:52 pm
by David Kilpatrick
SSS off, last use was studio flash. I also took some shots with the Sigma APO Macro 70-300mm but those are so much smaller in scale - however, it's much sharper than the 500mm f/8 RF. I've never managed to get any truly sharp image with the 500mm, despite having three different ones over the years.
David
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 2:52 pm
by Greg Beetham
I think it's asking a lot of a camera lens to produce a sharp photo of something so small enlarged to such a large size on screen. If I were to think of making such a large image of the moon I think I'd think seriously about using my 1500mm f6 lens.
Greg
Re: 500mm RF mirror on A77 - Moon
Posted: Mon Dec 12, 2011 7:23 pm
by Argonaut
Although I used this lens for a long time, and got many good shots on chrome, it did not hold up well enough with my a55. I sold it and used the money to buy the Minolta 100-400 APO. Good trade. (time to update my profile.....)