pwn posted:

Awesome, thanks for clearing that up.

Thom Hogan posted:

What's a t/stop? Well, an f/stop is a theoretical aperture (length divided by opening). A t/stop is the actual transmission property of the lens, and it's almost always lower than the marked f/stop because each air/glass transition in the lens is robbing just a bit of light.

DanTheFryingPan posted:

Don't worry, there's always the t/stop.

Beastruction posted:

What about zooms in the pre-computer-lens days? They'd have to be constant-aperture because there would be no way to communicate a changing aperture to the camera's meter, right?

orange lime posted:

No, the poster above me has it right. The f/number is a mathematical ratio comparing the physical diameter of the aperture to the focal length of the lens (f). An f/2 lens has a numerical aperture of half the focal length, and so on -- a 100mm f/4 has a 25mm diameter aperture. Light falls off with the square of the distance it travels, but the area of the aperture increases with the square of the diameter*, so the ultimate effect is that any lens set to f/2 will cast the same amount of light onto the film plane -- whether it's a fisheye or a normal lens or a super-telephoto. Light falloff through the optics is a factor in the actual amount of light reaching the film plane but most of the time it's negligible.

The reason that we can't make 10-600mm terrorzooms is because each end of that focal length range requires vastly different optics, many of which work at cross purposes to each other -- nothing to do with the aperture. The reason we can't easily make f/1.0 lenses (besides the progressively larger pieces of glass you require) is primarily because of spherical aberration that goes absolutely nuts when you start using the outer edges of a lens.

Most zoom lenses have a smaller maximum aperture at the long end because the aperture can't open beyond a certain size, which is a smaller fraction of the focal length at the long end than at the short end. With lenses that maintain a constant aperture, what is actually occurring is that the designers have made a conscious choice to limit the aperture's opening at the short end in the interests of sharpness. Your 70-200 f/2.8 could theoretically be a 1.4 at the short end, but it would be hazy and soft if not outright uncorrected.

</optics rant>

*If you remember high school math, you will be saying "but the formula is pi(r)^2!" Yes, area actually increases with the square of the radius. The diameter is of course twice the radius, and this is why full stops are separated by the factor of sqrt(2) = 1.4. Ie., each time you increase a stop and halve the light, you are dividing the diameter (multiplying the f/ value) by a factor of 1.4:
1
1.4
2
2.8
4
5.6
8
11
16
...

spf3million posted:

I've always wondered why they didn't make one of the 2.8 zooms faster at the wide end. Ok, maybe they'd be less sharp, but if you stopped down would it correct this while still having the option of shooting at wider apertures when needed?

FasterThanLight posted:

They should just need some kind of mechanism in the lens that moves the prong as it zooms, right?

Augmented Dickey posted:

Yeah, this is basically what my question boils down to.

ease posted:

Is that an E-10 with a M203 launcher attachment?

DanTheFryingPan posted:

Don't worry, there's always the t/stop.

Ringo R posted:

Augmented Dickey posted:

what's the total effective focal length for this setup? IIRC the E-10 uses a pretty tiny sensor so it seems like it must be really long.

quote:

TCON-300S Kit Kit includes lens (TCON-300), hood and support arm, it provides a x3.0 conversion of focal lengths giving a longest telephoto equiv. of 420 mm at just F2.8.

Cyberbob posted:

Just what the world of photography needs, more camera lenses shapped like rocket launchers.

quote:

PhotoSplash Photography
Hello Zoe,

Don't risk your corporate photos to a well-meaning employee just because they have a pretty good camera. If Zoe Quinn Photography is to maintain a professional image then your photo, lighting, colour correction and cropping must be done professionally.


"Rule #1 - If the image will be seen by the public,
get a pro to take the shot. "

At PhotoSpash we're making professional corporate images more affordable than ever. For a limited time we're waiving all post-production fees. This typically results in about a 28% savings!

If this interests you, all we need to do is discuss your photographic requirements and I'll send you a firm quote valid for 30 days showing your actual savings. Book your shoot for any date in 2010 to take advantage of this offer. (Reference promo code "FPP04")

Considering hiring the services of a photographer? Be sure to read the "10 Most Important Things To Know Before Hiring A Photographer". Click here to get it now. Dan, whether you choose to do business with us or not, you'll find it a quick and interesting read.

Reading this far suggests to me that you may have some pictures in mind. Have a look at my services and samples of my work then give me a phone call. If you prefer, go ahead and reply to this email. I'll get back to you in a flash!

Regards,
Michelle Manzoni
Photographer, PhotoSplash Photography

quote:

Before you hire a photographer for any reason you should be prepared to ask
some pertinent questions to insure a successful outcome. I have assembled a
guideline to help you get the results you’re looking for the first time. In many
cases, you don’t have the option to go back and do the shoot over again if the
images are unsatisfactory.

1. Most importantly, do you like the photographers work? Ask for a portfolio of
images that is relevant to what you need shot. If you want product shots for your
business don’t settle for landscapes or wedding samples. In fact, an experienced
photographer will have a portfolio for each category.

2. Does the photographer offer good value for the dollars paid? You need to
make an evaluation of the cost vs. the time and number of images they are
willing to provide.

3. Does the photographer offer you full rights to use the images as you wish?
Read the agreement carefully. Some photographer’s contracts preclude you from
using the photos for resale or public advertisements without paying a
substantial royalty fee. We don’t think that’s right.

4. Does the photographer provide a clear and concise contract which states
exactly what is being provided? Is travel, lodging etc. included or is it an extra
fee? Is there a distance fee? Is there an additional cost for weekends, evenings or
overtime?

5. How many hours will the photographer be present at the shoot?

6. Will they be the actual photographer for your shoot or will it be an “associate”?

7. Does the cost include editing, cropping and colour correction or is all that
extra?

8. Are the photos delivered to you on photo paper or as a digital download?

9. How long after the shoot will your photos be ready to view?

HPL posted:

She shoots Sony, so that instantly discredits her as a professional.

seravid posted:

Not trying to white-knight the brand I use, but "Canon and Nikon OR DEATH" can get pretty tiring.

Ol Uncle Anime posted:

I just got the best e-mail.

orange lime posted:

Phenomenal photos she has. Why does she call you "Zoe" in the greeting and "Dan" in the body of the letter?

I'm irrationally mad at her for promoting the idea that photographers should give away their rights to their photos. Then again, (1) she probably has nothing else to differentiate herself from the "employee with a pretty nice camera" (jesus christ that's basically exactly what she is) and (2) I wouldn't want my name to be associated with photos of that quality anyway.

Ol Uncle Anime posted:

do I troll her now?

Whitezombi posted:

10. Does the photographer know how to count to ten?

Ol Uncle Anime posted:

So I decided to head on over to her website