alex_culiuc

I've noticed two yellowish stripes appearing along the longer side of

prints from Fuji Frontier (model 350, if I recall correctly). This is

especially noticeable in highlights and in areas with more or less

continuous areas of same color (especially snow and sky).

I have absolutely the same problem with my obsolete Acer 2740 film

scanner -- supposedly this is caused by a dirty lamp inside the

scanner. Does the same thing happen in the minilab's internal

scanner?

One more piece of the puzzle. I noticed these stripes on prints from

Fuji Superia Reala 100. A friend who shot along with me pretty much

the same snow scenes on Kodak ProFoto (a cheap professional film sold

outside developed countries) had nothing similar in his prints

(printed at the same lab, maybe a day after mine prints).

The image I'm attaching shows a somewhat exaggerated view of what

these stripes look like -- actually this is a scan from my film

scanner (with boosted contrast and saturation to make the stripes

more visible), but it's the same effect I see on prints.<div></div>

<p>A few questions to Tom Burke and others who have both Sigma

24/1.8 and Canon 17-40/4L (or maybe another Canon wide-angle prime

or L zoom):

<ol>

<li>Which has an edge wide open (Sigma f/1.8 or Canon around 24mm at

f/4)?

<li>How does Sigma perform stopped-down to 2.5~2.8? Center and

corner sharpness? Chromatic aberations? Light fall-off?

<li>At which aperture does the Sigma achieve peak performance? At

that aperture (say 5.6), is it better than the Canon zoom at the

SAME aperture (5.6)?

<li>How fast is it focusing?

<li>How difficult is to get used to the Sigma MF/AF switch?

<li>How big does the lens FEEL compared to the Canon?

<li>How well is it built?

</ol>

<p>Additional comparisons of the Sigma to any the following Canon

lenses are also very welcome: 50/1.4, 28-105/3.5-4.5, 28-135IS, 20-

35/2.8L (I either own or have used them). I am especially interested

in comments regarding the performance of the Sigma @f/1.8~f/2.5

compared to 50/1.4 @f/1.4~f/2.

<p>Here is the reasoning for why I'm looking at this Sigma lens:

<p>I have the 17-40/4 and the 50/1.4 (among other lenses) on an EOS

5. I love the low-light abilities of the normal lens, and the

perspective the zoom gives at 20-24mm (it's great at 17mm for

landscapes, but very difficult to use for group people photography

as faces placed at the edges come out elongated and otherwise

distorted). I'm planning to move into digital within the foreseeable

future (1 year?), hoping to see an affordable 8mp 1.3x crop camera

introduced at Photokina (the elusive 3D every amateur is dreaming

of).

<p>The 50/1.4, even mounted on a film body feels at

times "telephotoish", on a cropped sensor it will transform into a

short telephoto (65mm on a 1.3x sensor, or 80 on a 1.6 body). I will

certainly welcome the "addition" of a fast portrait prime to my

arsenal, but will miss low-light, handheld, no-flash event

photography.

<p>So I reason that the 24/1.8 is a very good candidate to become

the perfect low-light event/PJ photography lens. On a film body, it

would not distort faces and objects at frame edges too badly.

Mounted on digital, this lens would transform into a fast moderate

wide angle lens (31mm on a 1.3x sensor, 38mm on a 1.6x).

<p>For landscape photography, I�d probably continue using the 17-

40/4L (due to its versatility).

<p>Please do not suggest the Canon 24/1.4L � it�s way too expensive

for me. Same goes for 24 TS-E (I want that lens badly, but for a

ompletely different purpose than the Sigma). However, any comparison

of this Sigma with Canon primes (28/1.8 and /2.8, 24/2.8) are more

than welcome.

When you run NeatImage with strong noise-removing setting on a VERY noisy image, you end up with ABSOLUTELY the same results. In NeatImage it can be even more pronounced -- imagine an absolutely smooth skin (smoothed by NeatImage) with such streaks and lines appearing on cheeks and on the forehead -- on screen, at 100% they look quite disturbing.

My guess is that you ran the PhotoShop RAW converter with some sort of noise-removal featured activated (this is quite obvious -- the PhotoShop RAW version looks much cleaner than the Canon RAW version).

70-200/4L may or may not be TOO HEAVY... In my experience, it depends if you shoot in horizontal (not heavy) or vertical (somewhat heavy) positions.

When I set my EOS 5 + 70-200/4L (no collar) on tripod (Bogen 3001 + 486RC2) in vertical position, I have to tighten the quick release plate to the extreme (to the point I'm concerned about damagin the body's tripod mount), otherwise the lens will rotating slowly on the plate. No such problem when shooting horizontal pics.

The solution I use: tilt the camera to the right (shutter button down) when shooting vertical photos, instead of left, as it is usually done. In this case the QR tightens itself naturally.

An even better solution for my problem (and a cheaper one than the collar) would be to buy the Bogen 3157NR Anti Twist Plate (has an additional lip to prevent camera twist).

I've just purchased the 1.4x TC, but didn't have the chance to check how badly it aggravates the tilting problem (it obviously should). If you are planning to buy the original 300/4L (as I am), don't hurry buying the collar for your 70-200. AFAIK, the 300/4 comes with the same collar as the one used on 70-200/4.

Again, if you have a better tripod head than I do, you might not experience the inconvenience I've originally faced (before started tilting the camera to the left).

Shun, I perfectly agree with your reasoning (decide what you want to photograph and then decide on the lens).

I simply haven't mentioned in the original post that there are other uses that determine my decision to buy the 70-200/4 (portraits, "compressed" city scapes, event photography -- in that order). So no, I'm not choosing the lens first, I'm just considering how useful it will be for uses other than those for which I'm buying it.

Thanks to everyone for answers and suggestions. Eager to read some more!

I am about to buy a Canon EF 70-200 f/4L. Thanks to photo.net and a

few other websites I KNOW this is a great lens. However, I�m

wondering how useful is it in nature photography?

Right now, for me "nature" means mostly landscapes (mostly forests

and plains, sometimes mountains), plus some close-ups of plants -�

all I have right now is a 28-105 on a EOS 5. Back to the 70-200: on

the short side 70mm is not very good for "traditional" landscapes

(the perspective lacks depth, "doesn�t look 3D", so to say). On the

long end, 200mm is not nearly enough for wildlife photography -- for

that purpose, may EVENTUALLY add TC 1.4 and, if all goes well, the

300 f/4 L (an expansion path based primarily on articles and comments

by Bob Atkins).

Obvious questions: if 70-200 is not pariculary good for landscape or

wildlife photography, what is it then good for? What are

the "generally-accepted" uses of a 70-200 (without TC) in nature

photography? How about original uses?

I would greatly appreciate if you could give links to nature photos

taken with lenses within this interval of focal distances.

I'm closely looking at the Bogen 3413 QR Pro Ballhead, and would

appreciate comments on this ballhead. There are a few discussions of

this ballhead, but none contained comments based on long-term use

(not surprising, as this ballhead is still relatively new).

I would especially appreciate opinions from people who have

experience both with 3413 QR, as well as with 3262 QR and/or 3055 QR,

as these two seem to be the most likely alternatives to 3413.

I've already made my choice regarding the legset: Bogen 3001 Pro.

I'll be using the tripod most likely while hiking. The heaviest

camera-lens combinations I'm planning to put on the tripod is an EOS

5 with a 70-200L/4 (with a 1.4 TC eventually), or maybe EOS 5 +

300L/4 (+ TC) if I get rich enough to buy this lens (most likely not).

I welcome any suggestions regarding other lightweight tripod-head

combinations, other than 3001 + 3413. However, take into account that

$150 is the max I'm about to spend -- no Gitzo tripods and Arca Swiss

ballheads please!