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Explorer
13th of January 2004 (Tue), 12:51
I have been surprised to see how fuzzy some of my shots have been with my new Rebel using the kit lens at its widest setting, 18mm. On searching this forum for suggestions, I noticed the following response from 2001 regarding the D30. Is it still necessary on the Rebel to zoom in to the maximum level to focus and then zoom back again to recompose the shot to get sharp images? If so, it seems rather a clunky procedure!

Explorer

Re: Disappointment with D30

Hi,

I read with interest your article about your new D30. I must say I experienced the same shocked emotions the second I took it out and used it. Whatever you do, do not send it back! This camera will make you money quicker than you can spend it. However, this will only happen when you learn it's weaknesses and how to overcome them.

Firstly, there is a disgraceful focussing problem with this very expensive pro camera. When you focus at wide angle the camera does not and never will get it right. Unfortunately, you need to zoom in at maximum range and re-compose back to wide to get focussed. While this is a pain, it works beautifully and the images are pin-sharp. Also, use the centre of the three focussing selectors as a permanent setting - works great. I use a sigma 24-70 and get magic results. Also, the first real shock was the soft images which appear on the lcd screen. It is widely reported and covered that this is deliberate on the part of Canon, and I agree with the decision. You do get to know when an image is out of focus or sharp using the lcd. When loaded into ps the images practically jump out at you after un-sharp masking.

The bottom line is that I work as a freelance photographer and much of my work is published in a local newspaper. I recently had my first front-cover and was delighted. Although the image wasn't the most exciting, it was sharp, perfectly exposed and hit the spot. All other images have been reproduced in colour and b&w in various parts of the paper and without a doubt the quality is exceptional.

Stick with it!
:? :?

slin100
13th of January 2004 (Tue), 13:14
The 18-55 lens is not parfocal. IOW, focus is not kept constant as focal length varies. Therefore, zooming in to focus likely may not improve focusing.

On the other hand, you probably need to first determine if the results you are seeing are due to misfocusing or due to other factors. I believe the kit lens is known to be a bit soft at the wide end, especially at or near wide-open aperatures. My suggestion would be to stop down the aperature one or two stops and see if you get better results.

Also, double-check your shutter speeds. Your images may be suffering from motion blur.

Explorer
13th of January 2004 (Tue), 13:28
Motion blur is not the problem as I have the Rebel mounted on a heavy Manfrotto tripod. Similar wide angle images taken with my Canon Elan //e film camera in the same way are super sharp!

RichardtheSane
13th of January 2004 (Tue), 18:54
What aperture are you using?

Jim_T
13th of January 2004 (Tue), 20:07
Can you post a full sized sample ?

I'm thinking you may be expecting $1000 performace from a $100 lens.. (Although most 18-55 shots I've seen are pretty good.. Perhaps there is a fault with either your lens or camera). An actual sample is the only way to tell....

Explorer
14th of January 2004 (Wed), 14:31
Here is one example where the crispness of the shot does not seem to match what I expected to see. (There was no wind to move the ferns and leaves around.)

taken at 1/5 sec, f13, 22mm, on a solid, Manfrotto tripod


http://members.shaw.ca/imagi/falls317.jpg

iwatkins
14th of January 2004 (Wed), 16:51
Actually looks fine to me. Not at all bad for a kit lens. Seems equally sharp almost up to the edges not withstanding the JPEG effects.

Only suggestion would be a slight increase in use of Unsharp Mask (USM) just to perk up the leaves a bit, but don't go mad. In addition maybe a slight increase in saturation to bring out the woodland colours.

The waterfall is a little overexposed as well, but that may well have been the effect you were going for.

But overall message is that the image looks reasonable sharpness wise, just needs some post processing with USM.

Cheers

Ian

RichardtheSane
14th of January 2004 (Wed), 16:53
Just out of interest, were you using cable release or self timer for the shot?

Explorer
14th of January 2004 (Wed), 16:58
Thanks for the suggestions.

I used the 10 second self-timer to help reduce shake when I took the shot.

iwatkins
14th of January 2004 (Wed), 17:23
Ahh, 10 second timer ?

If you use the Custom Functions, then you can set mirror lockup. This will lockup the mirror on the first push of the shutter button. The second will take the shot after only 2 seconds if the drive is set to self timer. This not only speeds up taking shots without a cable release, but using mirror lockup will reduce camera shake even further.

Cheers

Ian

Explorer
14th of January 2004 (Wed), 17:46
I don't see a Custom Function choice in the Rebel manual. I did have that choice on the Elan //e. Is mirror lock-up actually an available option with the Digital Rebel? If so, how do I access it?

iwatkins
14th of January 2004 (Wed), 18:01
Doh !

I do apologise. For some reason I read your first post and then from then onwards I assumed you were shooting with the 10D. The kit lens didn't give it away either. It's been a long day......

Anyway, the 300D (as we call it over here) doesn't have the mirror lockup facility. Sorry.

Cheers

Ian