Comments for adam reeve http://www.adamreeve.com geeks beats and treats Tue, 11 Oct 2011 23:01:05 +0000 hourly 1 http://wordpress.org/?v=3.2.1 Comment on Photo Tips #7 : Crop Factor Revisited by Ian http://www.adamreeve.com/2011/09/12/photo-tips-7-crop-factor-revisited/comment-page-1/#comment-11255 Ian Tue, 11 Oct 2011 23:01:05 +0000 http://www.adamreeve.com/?p=430#comment-11255 Re your last comment - Yes, I just noticed that the lens for the canon digital had a smaller 'hole' in the body end of the lens than Cora's old Minolta 35mm film SLR which has a Tamron zoom lens. - So they dont 'waste' all that light after all ;-) It pays to look rather than theorise Trants! Re your last comment – Yes, I just noticed that the lens for the canon digital had a smaller ‘hole’ in the body end of the lens than Cora’s old Minolta 35mm film SLR which has a Tamron zoom lens. – So they dont ‘waste’ all that light after all ;-) It pays to look rather than theorise Trants!

]]> Comment on Offsite backup with Crashplan by JoAnn Tropiano http://www.adamreeve.com/2011/10/11/offsite-backup-with-crashplan/comment-page-1/#comment-11254 JoAnn Tropiano Tue, 11 Oct 2011 21:59:21 +0000 http://www.adamreeve.com/?p=459#comment-11254 Hi Adam, I am interested in your offer if you still have room. JoAnn Hi Adam,

I am interested in your offer if you still have room.

JoAnn

]]> Comment on Photo Tips #7 : Crop Factor Revisited by adam http://www.adamreeve.com/2011/09/12/photo-tips-7-crop-factor-revisited/comment-page-1/#comment-11239 adam Wed, 14 Sep 2011 14:06:36 +0000 http://www.adamreeve.com/?p=430#comment-11239 So after a little research I think I was wrong about the perspective thing, so I deleted it. It's worth noting that the various lens types made specifically for APS-C sensors (Canon's EF-S mount for example) specifically have a smaller image circle, so this effect doesn't happen. It does mean, however, that they either work differently on a full frame (Nikon's actually crop the image digitally in a FF camera to remove the black borders!) or don't even fit (you can't put an EF-S lens on a Canon FF body). That said, the published length of these lenses is still at the 35mm standard, so you still have to apply the crop factor to get the effective length. I think they did this to avoid even more confusion :) So after a little research I think I was wrong about the perspective thing, so I deleted it.
It’s worth noting that the various lens types made specifically for APS-C sensors (Canon’s EF-S mount for example) specifically have a smaller image circle, so this effect doesn’t happen. It does mean, however, that they either work differently on a full frame (Nikon’s actually crop the image digitally in a FF camera to remove the black borders!) or don’t even fit (you can’t put an EF-S lens on a Canon FF body). That said, the published length of these lenses is still at the 35mm standard, so you still have to apply the crop factor to get the effective length. I think they did this to avoid even more confusion :)

]]> Comment on Photo Tips #7 : Crop Factor Revisited by adam http://www.adamreeve.com/2011/09/12/photo-tips-7-crop-factor-revisited/comment-page-1/#comment-11238 adam Wed, 14 Sep 2011 13:25:09 +0000 http://www.adamreeve.com/?p=430#comment-11238 As far as I know it's entirely literal. The distance between the mount and the sensor is the same (has to be, or it'd be out of focus), and the sensor is smaller, hence the crop. You're right about less distortion, most lenses are also sharpest in their center portion which is another advantage. Finally, much less chance of vignetting from filters or hoods. In terms of light capture, it is getting less on the smaller sensor, but the light incident per area is the same so the brightness of the image shouldn't be affected (as I understand it). That would show itself as needing a higher aperture on an APS-C for the same situation, and that's not something I've ever heard of. Smaller sensors do have their own problems of course, due to the smaller pixels and smaller distance between them - more noise, more clipping and less sharpness. As far as I know it’s entirely literal. The distance between the mount and the sensor is the same (has to be, or it’d be out of focus), and the sensor is smaller, hence the crop. You’re right about less distortion, most lenses are also sharpest in their center portion which is another advantage. Finally, much less chance of vignetting from filters or hoods. In terms of light capture, it is getting less on the smaller sensor, but the light incident per area is the same so the brightness of the image shouldn’t be affected (as I understand it). That would show itself as needing a higher aperture on an APS-C for the same situation, and that’s not something I’ve ever heard of. Smaller sensors do have their own problems of course, due to the smaller pixels and smaller distance between them – more noise, more clipping and less sharpness.

]]> Comment on Photo Tips #7 : Crop Factor Revisited by Ian http://www.adamreeve.com/2011/09/12/photo-tips-7-crop-factor-revisited/comment-page-1/#comment-11237 Ian Wed, 14 Sep 2011 09:04:17 +0000 http://www.adamreeve.com/?p=430#comment-11237 Ah, didn't realise this. Is it metaphorical or literal? If literal, it seems that the lens doesn't project all of its 'incoming captured image' on to the sensor. A consequence of that would be that it is only using the central portion of the lens - so less abberation + lens edge distortion, but the downside would be the sensor only gets 1/(1.6*1.6) = 40% of the incoming light. Ah, didn’t realise this. Is it metaphorical or literal?
If literal, it seems that the lens doesn’t project all of its ‘incoming captured image’ on to the sensor. A consequence of that would be that it is only using the central portion of the lens – so less abberation + lens edge distortion, but the downside would be the sensor only gets 1/(1.6*1.6) = 40% of the incoming light.

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