[Ubuntu]

^That is right out of the camera, but that's one of the better shots. I think I will toss about 50% in the end.

[newarts]

^That is right out of the camera, but that's one of the better shots. I think I will toss about 50% in the end.

Thanks, that's pretty impressive. It shows it is practical (not necessarily easy, but practical - a 50% keeper rate is great) to use a K-x with kit lens speeds in low light situations. The K-x 55-300mm kit seems a real boon for high school sports photography.

Dave

[newarts]

Back to the original post...

...would really like to get some great tight shots from the house..... I'm shooting from 60-70 feet most of the time....

The relationship between focal length and scene width at 60 feet is roughly:
25mm ~ 60' wide
50mm ~ 30'
100mm ~ 15'
200mm ~ 8'
300mm ~ 6'

For anything like a "tight" shot at 60' a 300mm lens will be required.

Dave

PS for an APS-C sensor, the field of view ratio (width:distance) is about
1:1 25mm
1:2 50mm
1:4 100mm
1:8 200mm
1:12 300mm

Say you want to take a photo of a scene 12' wide with a 100mm lens - how far must you stand back? - about 48' (1:4 - 12:48).

[Mike Cash]

Every year I do the annual recital for a traditional Japanese dance troupe and have the good fortune of being able to shoot it any way and from any place I please, which is about half from the first couple of rows of seats and about half with an elbow on the stage itself (from the edges, of course).

I do the bulk of it with Takumar lenses stopped down to about f5.6 and a shutter speed of 1/125 at ISO800 and no flash. For the ones that require flash I have remote flash set up on each side of the stage and fire them with radio triggers. Like I said, I'm fortunate to have a free hand and nobody questions it when I use flash, much less try to prohibit it.

This sort of shooting turns into a set of choices. You want to have as fast a shutter speed as you can, an aperture sufficient to give DOF to encompass what you need in focus, and an ISO as high as you can go without introducing an unacceptable level of noise. You have to find a balance that takes all three into consideration and yields acceptable results.

Regardless of the aperture you actually shoot at, a faster lens will make focusing easier (especially if you're using K-mount lenses, which practically everybody does), no matter whether you're using auto focus or manual focus.

Showing up for rehearsal is important, all the more so if they have the lighting set up the same as it will be for the actual performance. You need to be familiar with the performance to know what is coming up and what will be your best spot for getting a good shot. This allows you to take advantage of breaks in the action to move into an advantageous spot without annoying the audience while the show is going on. Working from the edges gives you more freedom to move front-to-back in the theater without blocking people's view or being overly distracting. Equally importantly, it gives you a chance to work out what exposure settings you're going to use during the show. If different parts are lighted considerably differently then you can work out each of the parts. Take notes about what settings you chose if you need to and refer to them during the show. A tiny keychain-type penlight is a handy thing to have on you in case you need to refer to your notes or the program during the show.

I shoot RAW because for one thing it means I don't have to pay the slightest bit of attention to white balance while I'm shooting; I batch correct each dance in Lightroom, a process which involves minimal time and fuss.

The real key thing to work on is improving your access and freedom of motion during the show, and that involves improving the performers' understanding of how that enhances what you are able to provide them in terms of photographic remembrances after the show. If they're satisfied with having a bunch of stuff shot from one fixed location in the audience, then that's what you'll be stuck doing. To my mind that provides output so uniformly dull that I would only do it if a family member were in the show.

You already work backstage; don't forget that the goings-on behind the scenes make for photographic opportunities arguably even more compelling than what is happening on the stage. There are wonderful shots galore waiting to be taken back there. As so few people have access to that sort of thing while practically anybody can shoot from the audience I would suggest that you make the most of the unique opportunity that provides you.

[Emily]

Newarts reply-VERY helpful thank you! As well as everyone else! There are so many options out there and it's hard to figure out what is compatible with pentax, if it's not pentax brand. What I've been shooting with the standard lens has made me quite happy, but I would like to be able to be further from the action and still be able to shoot that 5'x5' scene they're performing on stage.

[Lowell Goudge]

Just to expand on newarts a little

consider the following

Image size = subject size * Focal length / distance

this holds true for any lens as long as distance is much greater than focal length (i.e. more than 10X)

your sensor is 16 x 24mm (roughly)

[newarts]

Just to expand on newarts a little

consider the following

Image size = subject size * Focal length / distance

this holds true for any lens as long as distance is much greater than focal length (i.e. more than 10X)

your sensor is 16 x 24mm (roughly)

Thanks Lowell.

As a formula for Pentax cameras (modified for easy mental calculation):

f ~ 25 distance/width

D:W Focal Length
1:1 25 mm
2:1 50 mm
4:1 100 mm
8:1 200 mm


I used 25 rather than 24 because many people know the multiples of 25 and the estimation errors are small for this purpose.

Dave

[Lowell Goudge]

Thanks Lowell.

As a formula for Pentax cameras (modified for easy mental calculation):

f ~ 25 distance/width

D:W Focal Length
1:1 25 mm
2:1 50 mm
4:1 100 mm
8:1 200 mm


I used 25 rather than 24 because many people know the multiples of 25 and the estimation errors are small for this purpose.

Dave

just keep in mind the units. focal lengths and image size are in mm. all units in the equation need to be the same therefore express them as 0.1 for 100mm and 0.025 for image width so you have everything in meters.

I won't even think about conversions to feet.

[newarts]

just keep in mind the units. focal lengths and image size are in mm. all units in the equation need to be the same therefore express them as 0.1 for 100mm and 0.025 for image width so you have everything in meters.

I won't even think about conversions to feet.

Lowell is right, units must be consistent, but if things are presented as ratios, then units cancel:

Focal_length/Sensor_width = Subject_distance/Subject_width

Now all that matters is that units for focal length and sensor width are the same, while those for distance and width needn't be those used for sensor and focal length but must also be the same.

So millimeters can be used for focal length and sensor width, while distance and width can be feet, meters, yards, KM, whatever.

The equation I gave earlier might better have been written:

F_mm = 25_mm Distance/Width

to remind us of the units for focal length.

Dave