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10-02-2013, 01:13 PM   #91
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Nice shot.

Better the eaves on the porch than in the bedroom. For the last week I've had a huge huntsman spider roving around my bedroom, and evading my best attempts to kill him.

10-02-2013, 01:26 PM   #92
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QuoteOriginally posted by rawr Quote
For the last week I've had a huge huntsman spider roving around my bedroom
who you have in your bedroom is ....

absolutely none of my business!
10-02-2013, 02:08 PM   #93
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I'd prefer almost anything else in my bedroom, trust me.
But recently a huge spider has the best I can do. Sad but true.
10-13-2013, 09:28 PM   #94
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LED lighting is now the norm for places I shoot - the colors are attractive
but can play havoc with digital photography -
please see:

Modern LED Stage Lighting & photography problems ( 1 2 3 ... Last Page)

Friday night was a bigger venue with very good lights and lighting person -
but strong LED lighting was used a lot -

Red, Blue LEDs and the combination Magenta, are real difficult for JPG compression (as discussed in the linked thread)

normally with JPG compression the magenta in the face would have made it go mushy - almost as if it were out of focus -

as would this shot -


One can still get reasonable compression with JPG and not lose details - by turning chroma sub-sampling Off -
(please see Posts #155 and #156 (links) for more discussion on this)

But I have found some hosting sites like Picasaweb either re-compress or re-sub-sample uploaded images - with resultant degradation -
this is the same shot hosted on Picasaweb -

EDIT to ADD -
Note that the Picasaweb image is now the same - I managed to remove the auto-enhance and disable it for future uploads
(please see the EDIT to ADD in Post #96 below)

Fortunately I saved a copy of the problematical Picasaweb auto-enhancing -
so one can see the original problem -

(when I saw that - I even re-posted the shot with added (over-)sharpening - but to no avail...)





Digital photography difficulties aside - even though the strong colors are attractive-
it's still hard to beat regular white incandescent lighting - from the same gig -



Last edited by UnknownVT; 02-28-2014 at 11:01 AM.
10-14-2013, 03:48 PM   #95
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QuoteOriginally posted by UnknownVT Quote
it's still hard to beat regular white incandescent lighting
A big amen to that. Sadly indandescent is becoming rarer every day.

I've also noticed recently that some music sites that host photogralleries are using the Google PageSpeed service, or perhaps just the Google mod_pagespeed Apache plugin. Similar to Picasa, it also seems to sometimes attempt ugly JPEG 'optimizations' on the fly, as well as stripping JPEG metadata out from displayed images sometimes. It's a nuisance.
10-14-2013, 10:33 PM   #96
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QuoteOriginally posted by rawr Quote
A big amen to that. Sadly indandescent is becoming rarer every day.
Yep, that's the way of the world, unfortunately most people including lighting persons do not realize the difficulty (in digital photography) with the spikey spectrum/color distribution of LED lighting -
they are just impressed with RGB they can get 32 million colors.......

I might hazard that a lot of photographers either discard the shots with magenta, mono-red or blue, or just give up and make the pics b&w.

QuoteOriginally posted by rawr Quote
I've also noticed recently that some music sites that host photogralleries are using the Google PageSpeed service, or perhaps just the Google mod_pagespeed Apache plugin. Similar to Picasa, it also seems to sometimes attempt ugly JPEG 'optimizations' on the fly, as well as stripping JPEG metadata out from displayed images sometimes. It's a nuisance.
Thanks for that - yes, PicasaWeb is part of Google its url is https://picasaweb.google.com/ may be that's why they are doing the same thing - they ought to have a setting that disables any "optimization".

Up to now Flickr does not seem to re-manipulate uploaded shots -
here's that same photo uploaded to Flickr:

on Flickr .................................................................................................................... over-sharpened version of same image on Picasaweb


on Flickr .................................................................................................................... same image on Picasaweb

EDIT to ADD -
notice there is now NO color difference between the versions of the photos on Flickr and Picasaweb !! (the Picasa images are slightly over-sharpened)

Just so the severity of problem can be seen, I did save a copy of the Picasaweb auto-enhanced version:


I discovered a discussion thread that gave an unofficial and obscure way of disabling the Auto-Enhance in Picasaweb -
as mentioned one CAN disable the Auto-Enhance in Google+ - but NOT in Picasaweb -
the trick is to join Google+ - disable auto-enhance on existing posted photos -
that cures the problem for existing messed up photos - as evidenced above.

And the real bonus is if one disables auto-enhance for all uploads -
after cancelling Google+ (as I don't want/need the social networking)
the auto-enhance remains disabled -
I tried uploading several problematic photos and they were all left untouched.

If anyone's interested this is the thread that helped me

Last edited by UnknownVT; 02-28-2014 at 11:05 AM.
10-15-2013, 12:04 AM   #97
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Sadly the images look much worse on Picasaweb.

It's not even an embedded color-space issue or anything similar, it seems, since all the images you've posted report themselves as sRGB. It's not even a browser issue either, since those Picasaweb image colors are as wrong in IrfanView or MS Paint as they are in my browser.

It does seem that the Picasaweb's image handler itself is doing some very poor JPEG processing. I wonder if the same problem shows up if an image is posted on Picasaweb's sibling, Google +. G+ is supposed to be very photography friendly. If Google gets the image right in G+, but wrong in Picasaweb, the Picasaweb admins may have some explaining to do.
10-15-2013, 09:04 AM   #98
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QuoteOriginally posted by rawr Quote
It does seem that the Picasaweb's image handler itself is doing some very poor JPEG processing. I wonder if the same problem shows up if an image is posted on Picasaweb's sibling, Google +. G+ is supposed to be very photography friendly. If Google gets the image right in G+, but wrong in Picasaweb, the Picasaweb admins may have some explaining to do.
Being all the same Google group -
it is probably likely they all use the same processing components -
it's my understanding on joining Google+ any existing Picasaweb account is supposed to be merged into it
(and I doubt if they would actually backtrack to undo all their sub-"optimization" of photos - some people have 10's of thousands of photos).

Picasaweb was/is Google's premier site for photos -
there's even Picasa the photo editor which is/was very highly regarded.....
it had built-in sharing and tagging for Picasaweb, and now Google+

It looks as though Flickr has had some policy/limit changes since I looked years ago -
it now appears as if it has a free 1TB limit -
so I may switch over to Flickr to post/host my photos.

Pity, as I have over 6 years' worth of processed photos (10's of thousands) invested in Picasaweb -
but with the prevalence of LED lighting and the apparent mandatory automatic sub-"optimization" by Picasaweb
it seems some of my best efforts (to mitigate the problem - which can be quite substantial)
are UNdone by them (or worse) when I post a photo to Picasaweb.

EDIT to ADD -
There is a way to Disable the Auto-Enhance by Google - but it is in Google+ only - I cannot find it on Picasaweb


Last edited by UnknownVT; 10-15-2013 at 02:37 PM.
12-12-2013, 12:34 AM   #99
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I have to photograph objects occasionally - basically they are merely utilitarian/functional shots.

For years I've admired knife photography - but also realized when I tried it myself that there was a lot more involved -
especially in lighting....

Eric Eggly - Point 7 Photography set up at the Blade Show.

My main difficulty was in mirror polished blades - as the name suggests they are like mirrors so would reflect - even the photographer.
So it's always been a challenge.

I tried things like light tent/boxes - although they did give soft even lighting -
the problem was mirror finish inevitably would reflect the seams of the box,
or the photographer - since they had a restrictive opening....

Recently I managed to get a relatively effective lighting set up -
for the additional cost of $1!
It was simply a white foam art board that I bought from a dollar store.

It normally stands as a background so that it's reflect light back onto the scene -
but for mirror finish I tilt it forward so that it would lean on either the two desk lamps, or literally on my camera, or forehead.


This was a relatively straightforward shot -
I merely varied the tilt of that white foam board until I got rid of any unwanted reflections
and getting the best blade modelling....

The K-5 being a dSLR with real optical through the lens viewfinder -
allows me to make micro-adjustments until I see the best angle/shot.


This was also a straight forward shot - but required more post processing to bring up/enhance the wood grain.

Word about color balance - I use two 6500K "Daylight" CFLs (compact fluorescent spiral light bulbs) - 26watt rated @ 100watt equivalent.

Although they are supposed to be daylight - the K-5 on daylight white balance show these to be a bit too blue -
whereas 5000K "sunlight" CFLs tend to be a bit too yellow/pink.

I shoot AWB which correct the balance somewhat - but it is not always as accurate as I'd like - so I correct in post processing.

I use gray-point correction on that blades or if I shoot a white background the white point on the background.

For the black background I place the knives on a piece of black craft felt material -
but the pic always shows the texture - so I either do a fill with black to get rid of the distraction - but often results in some mottled gray patches -
so I have to deselect the knives and use -100 brightness and -100 contrast to blacken the background.


this blade has a polished satin finish - so no where near as difficult as mirror polish -
but hard to convey its sheen - I think this was reasonably successful -
the white foam board was left standing - the the blade was lit with direct lighting and the angle was so the blade reflected the white board background.



12-12-2013, 02:28 AM   #100
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Well executed shots, although there are some JPEG jaggies around the place (eg the top and bottom edges of the knife in the 2nd last shot) that are probably only showing up here in the small Photobucket images.

That last knife looks very well designed and crafted, and quite exotic.
12-12-2013, 09:15 AM   #101
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QuoteOriginally posted by rawr Quote
I'd prefer almost anything else in my bedroom, trust me.
But recently a huge spider has the best I can do. Sad but true.
Have no fear, she is harmless....and just went under your bed to have a few (hundred) babies!





Sweet dreams!
12-12-2013, 11:38 AM   #102
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QuoteOriginally posted by Rupert Quote
Have no fear, she is harmless....and just went under your bed to have a few (hundred) babies!





Sweet dreams!
My daughter hates me now.Thanks!
12-12-2013, 02:00 PM   #103
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QuoteOriginally posted by rawr Quote
Well executed shots, although there are some JPEG jaggies around the place (eg the top and bottom edges of the knife in the 2nd last shot) that are probably only showing up here in the small Photobucket images.

Thanks rawr as always for your invaluable comments and discussion.

Jaggies - yes, that has always bothered me - but I just put it down to images being digital and having to display them on square pixel matrices.

But when you mentioned JPEG - I thought I had chosen a good compromise of compression size and quality.

So I re-shot the knife this time in uncompressed RAW DNG - then processed in PDCU (Pentax Digital Camera Utility) 4.35 - cropped, then re-sized to 640 pixel width and saved to Uncompressed TIFF -
I could see the jaggies in that image - but once I did my normal processing and then sharpened the image -
BANG! the jaggies became more obvious - I saved to uncompressed PNG (and TIFF but PhotoBucket doesn't seem to accept TIFF)


Uncompressed PNG from original RAW/DNG cropped, resized and converted in PDCU saved as uncompressed TIFF.

The jaggies are pretty obvious along the top/spine of the blade.

Here's a more conclusive experiment.

Opened new image with black background in editor - then drew a few thin straight white lines -
while I was doing that I could see the very obvious jaggies -
saved new image to uncompressed PNG -


So I think it is merely the (inevitable) nature of having to display on square pixel matrix displays.....


My very simple lighting set up -

white art foam board upright for most non-mirror finish.


board tilted leaning against the lamps - but often rests either on my camera, or lens barrel, or extended finger, or even head.......


QuoteOriginally posted by rawr Quote
That last knife looks very well designed and crafted, and quite exotic.
Thanks - that's a Mcusta 113D - "Tsuchi"
- not too expensive in the world of collectable knives -
in fact can be regarded as really good value for what one gets -
"MCUSTA stands for Machine Custom Knives"

If it's of any interest I have a review -

Review - Mcusta 113D - "Tsuchi"

where one can see some shots with flesh colored reflections!
(so you can tell I only recently figured out the lighting)

Thanks,

Last edited by UnknownVT; 12-12-2013 at 02:08 PM.
12-12-2013, 03:28 PM   #104
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QuoteOriginally posted by dansamy Quote
My daughter hates me now.Thanks!
I love spiders and shooting them...but don't want to get too wrapped up in it!




Regards!
12-12-2013, 04:18 PM   #105
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In working with fonts and line art, anti-aliasing usually works to visibly reduce or disguise jaggies, or such stepped lines. I wonder how one could implement a similar solution here?

Do the jaggies on the knife look any better (or worse) depending on which camera you use - eg the K-5 vs the K-x vs one of your Canons? At the capture stage, even before any JPEG processing, the strength or weakness of the in-camera AA filter (and any other in-camera sharpening applied by the imaging engine) may perhaps be playing a role here. The camera with the weakest AA filter (or least aggressive sharpening) may give you a better start in processing such images.

I went looking for a simple jaggies solution, but unfortunately there isn't one The problem is widespread, and there are a lot of web discussions about it. These discussions suggest some interesting options though, from using masking to reduce jagged lines, to adjusting the re-sampling filter (bi-cubic, Lanczos etc) during any JPG resizing, altering the colour-depth, to using various other filters (depending on the graphics app), like noise reduction or CA reduction or 'despeckling' filters, to smooth out or disguise jaggies. There is even a promising tutorial on using gaussian blur and curves adjustment to smooth out harsh jaggies in bitmapped images. The simplest solution seems to be just to add a well blended drop shadow where possible.

But when you have high contrast surface edges, and are working with small JPEGs, jaggies do seem inevitable. It's a pity.

And thanks for the link about Mcusta. I'll have to look into them. Your photos of those on that knife forum are very well done.
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