Photographing DVD players

[SR071]

Hi All,

First post nerves at work...hope this is the right place to post.

I've been wanting to photograph the front panel of a dvd player for inclusion in an ebook I am writing, but every shot I take turns out totally unlike (in a bad way) the shots I see in magazines and brochures. It's not the light, it's the perspective/DOF/converging lines etc. I need to flatten out the image.

I have a 20D, and every lens from 24mm through 300mm at my disposal from f2.8 and up.

Can someone suggest ideal focal length and f-stop to get the professional look?

Thanks in advance! :)

[bolantej]

have any shots you can show us? maybe that could get it started, at least knowing how far you have gotten with it.

[SR071]

Sure - file attached - note how it kind of 'curves' towards the edges - sort of like a fish eye type shot..but not really. I don't exactly know how to explain it - but the lines aren't straight. That's the problem. Look particularly at the grate on top, it doesn't look right.

Thanks.

[JakeC]

Is that shot with a wide angle lens? If so you can limit barrel distortion by taking it with a telephoto like the 70-200.

[SkipD]

Something that many new photographers fail to understand is choosing focal lengths for perspective control. For example, longer focal lengths ("telephoto") are frequently thought of as tools merely to "get closer" to a subject. What is misunderstood - or totally unkown to the photographer - is how using a longer focal length lens can increase the relative size of background subject material as compared to the foreground (or main subject). Of course, the opposite is true with shorter focal lengths. The bottom line is that using different focal lengths - and changing the physical distance between camera and primary subject - can totally change the perspective of the image.

SR071 - it appears that you chose a focal length primarily to fill the frame at some arbitrary distance from the subject without regard to resulting perspective.

If you use a shorter focal length - and get closer to the subject to maintain the same image size for the face of the DVD player - you would increase the apparent distance between the front and rear edges of the DVD player, adding to the perspective distortion. You would probably see some distortion - curving - of the front face from side to side as well.

Choosing a longer focal length - and moving further away from the subject to maintain the same image size for the face of the DVD player - would compress the apparent distance between the front and rear edges of the DVD player, reducing the apparent angle between the sides. With a longer lens, the curved distortion of the front face would likely be reduced as well.

For the specific perspective control problem you seem to have, I would suggest that you use a lens with about three or four times the focal length that you used originally. This would require three or four times the distance between the camera and DVD player to maintain the same image size for the face of the player.

Choosing an aperture (f-stop) for depth-of-field control can also be a useful tool. A wider aperture (smaller f-stop number) will decrease the focus quality away from (closer to and further away from the camera) the primary focus point. A smaller aperture (larger f-stop number) will put more of the image (from front-to-back) in focus. If you are using flash as a lighting source, you will need to change the intensity of the lighting to allow you to choose a different aperture. This is because shutter speed has no real bearing on exposure when using electronic flash.

[chtgrubbs]

Most lenses, particularly zoom lenses, and especially wide angle zoom lenses, have barrel or pincushion distortion, wherein lines to the outside of the frame are rendered as curves. There is software which can correct this, but the best way is to use a longer focal length prime lens such as the 50, 85, or 100mm prime. Particularly good are the macro lenses which are highly corrected for distortion.

[EricKonieczny]

Wow great explanation SkipD. I do some product photography and know what to do for certain looks and angles, but you spelled it out nicely. :D

[Spirit]

Wow, great explanation Skip.

I just wanted to add though that I imported it into photoshop and used grid lines to see where the image "barrelled" (I couldn't see it), but all lines were exact (no distortion).

I don't know lenses so I can't comment, but my explanation would be the 4 front corners and the 4 back corners of the dvd don't line up, making the top appear as though it's slightly convexed or 'warped'.

Is there actually some distortion here?

[Avalonthas]

Im assuming u want a flat image of the front only and your problem is the angle of the side of the DVD player from corner to corner on the top of the DVD player?? well if thats the problem then here is the simple solution, your shooting it like a 3D object, where u want it to only appear 2D....hence your camera is not 100% level or flat with the horizon of the DVD player, which is why you are catching the top of the DVD player. You must also absorb that a lens is curved and thus even if it is positioned correctly, you still may see the top of the player because the light from the very top if bent from the outter periphery of the lens, into the center of the lens where your focal point is, and where the image is recorded. I will save you the highschool physics lesson, but an easy fix to such a problem if u cant get the lens/positioning arrangement how u want it, why not use photoshop to cut off the top of the player, thus giving you a flat surface. And if your making a book I would recommend you use a white background so it will look better with respect to your document.

I think this is what u want to accomplish with a flat 2D look even those this image was done in 3 seconds and looks horrible, if u spend more time in photoshop u can make it look nice. Your image is also not completely level, but thats an easy fix:

http://www.plasticentertainment.net/dvd.jpg
If this is not what u meant, then disregard this post lol

[SR071]

Hi Guys,

Thanks for the great explanations!!! I'm particularly impressed with SkipD's coments.

I've tried a 70-200 f2.8 set at 170mm. It gives the compressed 2D feel that Avalonthas talks about.

I tried moving the camera around for the 70-200mm range and found the straightest lines at 170 - so will stick with that in future.

I also set at f2.8 - as this blurred the background, and will blend nicely with the white cube I have for doing the photos. f2.8 gives me about 5cm of completely in focus dvd player - so i'm happy with this.

Please see sample shot of a different box i used for testing...turned out well methinks.

Thanks once again!

[PhotosGuy]

Great explaination, Skip!
Just for future reference guys, in the future, look at your subject from several different angles. When you see one that you like, put your tripod there! ;-)