Photography Advice and Tips Thread.

[dbaldock]

This is a question for anyone here who has built a light-box for doing close-up photography.


Is there a particular fabric that works better to diffuse the light from external lamps and provide even illumination?


I've got a group of Nikon & Tokina Manual Focus Lenses that I'd like to photograph, so I can put them up for sale (or trade in at a Camera Store).


Take Care,
David Baldock

[Skip]

Sounds like you want something that is inexpensive so if you have a white sheet hang it in front of your lights and that should work fine.  Actually anything that is white and semi transparent will work - the bigger the better.

Skip

[DeadBishop]

White ripstop nylon works well as a diffusion material.

[renfairephotog]

http://www.fortysixtyphoto.com/shop/crossbones/ No advice just a cool shirt aperture crossbones.

[dbaldock]

Stuck Pixels?

It looks like I've got several apparently Stuck ON Red and Green Pixels on my Nikon D90.  So, does that mean the Sensor will need to be replaced, or is there some sort of calibration procedure that can be done?  Is that something that an Extended Warranty will usually cover?


Take Care,
David Baldock

[DeadBishop]

Sounds like you have "hot" pixels.  Generally there is no fix for this, only replacement.  There are work arounds, where either the camera or post production software can map out the bad pixels, but that's not really fixing the problem.  An extended warranty should cover this kind of repair.

[Rani Zemirah]

I've been driving myself crazy the last few days trying to figure out how to simulate HDR using the available settings in CS4's Photoshop...  The color depth and intensities are fairly easy (just variations in the levels settings for the A and B channels in Lab color), but the tonal variations and luminance are making me want to tear my hair out!  I know I could just get the program and let it do a great deal of the work for me, but I want to know HOW it does what it does!!!  Gaaaaaahhhhh!!!

Gorgeous, work, btw...

Sorry if this should have been posted in a different thread, but I was here, the thread was here, and my frustration was here all at the same time.  DISharmonic convergence, perhaps...  

(above was originally posted in Picture of the Day, which is why it's contextually... odd)

[dbaldock]

I've been driving myself crazy the last few days trying to figure out how to simulate HDR using the available settings in CS4's Photoshop... 

Using Google Search, I found this:  http://www.tutorius.net/search/hdr+simulation+in+cs4/

Don't know if it's free, or a pay-type of tutorial.


(I run OpenSuSE Linux on my PC, so I don't use CS4 here.)

Take Care,
David Baldock

[renfairephotog]

I skipped CS4 so I'm not sure what all is there. CS5 has a new Adjustment call HDR Toning. Which is what I'm using now. It lets you do toning with one image. plus it has HDR PRO. which I haven't had time to test out yet.

[Rani Zemirah]

But... see... I wanna know HOW it's done... what settings they use with the Shadows/Highlights function, and how they tweak them, and what, exactly, they do to get the variations in local tonal ranges to produce the luminance that makes the photos look almost like they're... back-lit.  It has to do with tonal contrast, and I think there might be a Gausian blur filter applied at some point, as well, but there's something I'm missing...  

I've never NOT been able to figure out how to reproduce an effect in Photoshop, and I'm just not ready to give up yet!  I've got a few things I've been playing with, and the before and after shots are a lot different, but it's still not even close to what I see here.  None of the photo's I've used are my own work, though, so I've been hesitant to show them here, but they're just stock images that I've been using to experiment with, so I'll post a few, just to give an idea of what I've been able to figure out so far...  Hope no one minds!

Before:

After:

Before:

After:

Before:

After:

Before:

After:


Sorry... I've got my photobucket set to automatically resize all the photos when I load them, so none of these are the actual size I've been working with.  Obviously, the luminescent quality is eluding me, but then, I've been working with single images, although I'm starting to look at using blending modes with multiple layers to see if I can achieve the effect that way...  Frustration abounds!  

Oh... terribly envious of the CS5, btw, and I've only had 4 for about 6 months!!!   

[renfairephotog]

here's  a screen cap of the tone map(single image hdr) It might give you a hint. Most of the presets have contrast or saturation in the title.

[Rani Zemirah]

Edge Glow?!?  WHAT?!?  LOL  Oh, great... not an adjustment setting in CS4, although there IS a filter that will produce glowing edges...

OMG!!!  That's IT!!!  It's a simple freakin' filter effect under the Stylize settings!!!  It's not as sensitive as it could be, and it doesn't include the range or strength settings, but I can change the edge Width, Brightness and Smoothness, so we'll see what I come up with tonight... although I did wonder if Curves might be a part of the equation.  

I don't have anything like the Tone and Detail settings, though, but I can play with Tonal range in the Shadows/Highlights, Vibrance and Color Balance Adjustments, and it's possible I might just be able to puzzle it out before it drives me absolutely NUTS!!!    (yeah, I know... you don't have to say it...   )

You are... AWESOME, RFP!!!  Aaaaand I can tell I'm gonna be up all night again...  LOL  WewT!!!

Ok... just a few minutes of playing with Glowing edges...


The auto sizing is really bothering me, though, because a huge amount of detail is being lost here... have to do something about that tomorrow.

[Skip]

Curious if what your trying to do is HDR or more enhancing the color or color boosting?  If you are wanting to really make the colors be more vibrant than that is pretty easy to do in LAB.  I can help with that if that is what your looking for.

Skip

[Rani Zemirah]

Oh thank you, Skip, I appreciate the offer!  I'm good with Levels in LAB, though. That's where I started... (see quote)  

I've been driving myself crazy the last few days trying to figure out how to simulate HDR using the available settings in CS4's Photoshop...  The color depth and intensities are fairly easy (just variations in the levels settings for the A and B channels in Lab color), but the tonal variations and luminance are making me want to tear my hair out!  I know I could just get the program and let it do a great deal of the work for me, but I want to know HOW it does what it does!!!  Gaaaaaahhhhh!!!

I'm really just wanting to figure out what has been done to create the HDR effect, and how to reproduce it without using the various programs out there.  I like to know HOW things are done, and before there were programs created that did it FOR you, someone had to figure it out using the programs that were already available...  Vibrance, Saturation, Channels, Shadows/Highlights, Tonal Range and even Blending Modes all seem to be involved, and I'm very curious to know how, and more importantly WHY, each is set as it is, the correct sequence of adjustments, and what, exactly, each adjustment does for the end result.  Since there don't seem to be any manual tutorials out there, it's been trial and error on my part... mostly error, unfortunately.    LOL  

I actually began with LAB adjustment experiments, since that seemed the most obvious starting point, but that may be a later step (if it's a step at all), since the color enhancement actually seems to cause a huge amount of image darkening when using the Glowing Edges filter.  I'm now finding more success with using multiple copies of an image, but I still haven't been able to completely reproduce that... other-worldly effect of the HDR... so far.  I have some things that are getting closer, though, so I'm going to keep experimenting in my free time... because my curiosity gives me no peace!  I will happily apply any advice I receive, however!!!    

(edit)
I guess I should start recording my Actions, also, huh?  It would help if I had a list after the fact that I could look at and say "this produced this, and that produced that...". 

[Skip]

Hey Rani, I found a tut on HDR that you might like - http://www.backingwinds.blogspot.com/2006/10/how-to-create-professional-hdr-images.html - also here is a reference page for a bunch of tut's on HDR - http://tutorialblog.org/hdr-tutorials-roundup/.

I hope this helps, don't know it they explain why the steps lead to the end result but they seem to have the steps involved in the process.

Skip