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Forum: Pentax SLR Lens Discussion 3 Hours Ago  
Lens Cleaning Fluid Question
Posted By BigMackCam
Replies: 9
Views: 288
Thanks again :)

I'm an amateur when it comes to chemistry, I'm afraid... :o

I found the following file, but don't know how the information refers to >= 99% methyl alcohol. Is there a way for the layman to determine this based on the information therein?

https://sensorcleaning.com/Eclipse.pdf
Forum: Digital Processing, Software, and Printing 4 Hours Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Much appreciated, Tony. I'm starting to understand how variable the whole print world might be. Thankfully, for me, it's currently of minimal concern, but I forecast interesting times ahead if and when I might print more :o :p

Once again, I'm very grateful for your help and advice, and the time you've invested in this. Thank you :)
Forum: Pentax SLR Lens Discussion 5 Hours Ago  
Lens Cleaning Fluid Question
Posted By BigMackCam
Replies: 9
Views: 288
Good to know - thank you. Do you have a reference for this (e.g. link to the data sheet)?

Given that, my preference stands - even more so, in fact... Breath and a single-use, lint-free lens paper :)
Forum: Digital Processing, Software, and Printing 5 Hours Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Thank you, Tony, this makes perfect sense :)



Again, given your own use of 110cd/m2 and your appreciation of my differing environment, this makes sense. I'll start with your 110cd/m2 level, and see how I get on. It sounds like I need to keep it much lower than I'm used to, though.



Great info, Tony, and thank you for the attached images which make this all-too-clear. Given your advice that many papers will be close to D65, it seems like I might be better served by sticking to this colour temperature for all of my work unless I gain experience with certain papers that buck the trend. And, given my current situation, that's unlikely.

But what about luminance and gamma for printing purposes? Would you suggest broadly-applicable target levels for these? I see from your list of profiles 5000k @ 80cd/m2 - so is this what you'd typically switch to if you were preparing an image for printing? And if so, what gamma?



Tony, I can't thank you enough for all the information you've given me, and the patience you've demonstrated. I clearly have a long way to go, but I'm more educated than I was to begin with, and that's both reassuring and satisfying :)
Forum: Photographic Industry and Professionals 6 Hours Ago  
Film versus digital sales
Posted By BigMackCam
Replies: 63
Views: 1,713
Me too, but I fear we're in the minority. Almost everyone I know seems to use social media not just for sharing photos, but to become embroiled in discussions and arguments. In some respects, I guess photography forums like these are similar, yet the near-real-time nature of social media platforms and the wide-spread use beyond our narrow target audience here marks them as something apart.

I have no Facebook, Instagram, Twitter or any other social media accounts, nor any desire for them. I do, however, share some of my photos with friends and family via e-mail - and just very occasionally, here on PentaxForums...
Forum: Pentax SLR Lens Discussion 7 Hours Ago  
Lens Cleaning Fluid Question
Posted By BigMackCam
Replies: 9
Views: 288
I believe the issue with Sony isn't its lenses, but rather the sensor or the material covering this - hence why certain sensor gel sticks are designed specifically for Sony cameras.

You should be absolutely fine with Eclipse fluid for Pentax camera sensors - and any lenses, regardless of brand.

I will say, however, that after trying all manner of lens cleaning solutions, my favourite approach - unless you're actually servicing a truly filthy lens and all of its elements - is to simply breath on it and wipe very gently with a good quality, lint-free, single-use lens paper - or, if you prefer, a good quality lens cleaning cloth (note, you should always blow away any debris - even if it's not visible to your eyes - with a rocket blower first; alternatively, brush it away gently with a soft-bristled make-up brush). I've read occasionally that there may be acids in human breath that aren't ideal for lens cleaning, but personally, I feel that's absolute tosh considering the amount of contaminants floating around in our air. Anyway, this is what I now do for general cleaning. Otherwise, I use Zeiss lens cleaning fluid, or occasionally pre-moistened Zeiss lens wipes.
Forum: Digital Processing, Software, and Printing 8 Hours Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Again, absolutely not. I can use all the help I can get, especially from an experienced chap such as yourself! :o



For most of the time I'm at my PC, I'm at the breakfast bar in my kitchen with fairly bright daylight-colour LED lighting overhead, or daylight streaming in the windows (with little glare or reflection due to the position of my PC). In that environment, looking at other people's photos online and my own, things look good to me. I don't mean to suggest I'm using the appropriate luminance setting for calibration... Only that my screen, whilst relatively bright, reproduces photos that others share online with an intensity that I find pleasing, and when I edit my own photos and view them in this environment, they're broadly in line with everyone elses. I'm happy to consider and accept that my viewing preference is "too bright", and adjust accordingly. I will certainly try 110cd/m2 per your own profiling and see how I get on with it.



Thanks for these links, Tony. I haven't had a chance to do anything on the new machine and monitor today, due to other commitments... but I should get plenty of time tomorrow to experiment. I'll use these links to reference the white saturation and black level.



I'm utterly, utterly ignorant in terms of profiling for print, Tony (and only slightly less ignorant on ideal display profiling too! :lol:).

Most of the time, I view my photos on my laptop, external monitor, tablet and just occasionally on one of my (unprofiled, but manually adjusted to a reasonable degree) TVs. For my profiled device displays, I've been using D65 with a gamma of 2.2, since that seems to be recommended for general office and web use (and I therefore assume if there is any level of standardisation within the rest of the viewing world at large, it's likely to be this or close to it). As for luminance, I'll try 110cd/m2 and reference to those links you've provided.

I don't print at home (indeed, I don't have suitable equipment - only low-end domestic four-colour inkjet). I have just a handful of my own photos third-party-printed and hung on my walls at home. The colour match between those and what I saw in Lightroom - the software I was using at the time (I'm a Darktable convert these days :p) - wasn't bad, but nor was it especially accurate. I can only guess that the printing company (a large consumer-oriented printing firm, aimed at the general public rather than photography enthusiasts and professionals) did some tweaking on exposure at the very least (and possibly more), as they look decent enough to my eyes.

My future printing is also most likely to be via third parties, though I may start to use more photography-oriented printers. My choices on my printing oriented editing profile(s) were based on things I've read from various online articles. D50 seems to be very popular for print work, and I'd read about this in several articles (I forget which ones, but may be able to find them again). Same with the gamma, but less so.

I guess what I'm saying, in a very round-about way (though hopefully it's becoming obvious to you), is that I simply haven't a clue when it comes to profile calibration for print-destined work, and only a little more for display work :o



I like the idea of this, but given the rarity of my printing, it may be overkill. Currently, I feel like I'd prefer to have one (or two) general profiles that will get me "in the ball park" for print-destined images.

I wonder, do professional printing companies advise on the best profile calibration settings for editing that will result in a good match for their printing and paper choices? This is probably an unnecessary level of detail for my personal situation, but I can see that it would be useful.

Thanks again for your help and patience, Tony :)
Forum: Pentax Price Watch 13 Hours Ago  
B&H 12/12 Daily Deal-27 inch LG Monitor $105 discount - Regularly $250
Posted By BigMackCam
Replies: 4
Views: 200
I've edited the thread title accordingly.
Forum: Digital Processing, Software, and Printing 18 Hours Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Perhaps the calibration software would run in Linux under WINE? Or, alternatively, you could install Oracle VMWare and create a Windows virtual machine and run it under that...
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 1 Day Ago  
Best and worst of 2018
Posted By BigMackCam
Replies: 5
Views: 252
Oh my... Never underestimate the power of denial...
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 1 Day Ago  
Best and worst of 2018
Posted By BigMackCam
Replies: 5
Views: 252
Am I the only one desperate to buy a Yashica Y35 when they all turn up on eBay at silly-low prices? It's got to be worth it to see just how bad it really is :lol:

Considering earlier Yashica-branded "digital lomo" cameras, I find it hard to sympathise with anyone that bought a Y35... You could see that train coming off the rails miles away :o

EDIT: ... and here's one already, and in my home country too! :p I'm kind-of tempted :lol:

https://www.ebay.co.uk/itm/Yashica-Y35-digiFilm-Camera-With-4-Films-brand-ne...CA7M:rk:1:pf:0
Forum: Photographic Equipment for Sale 1 Day Ago  
For Sale: Test post - please ignore
Posted By BigMackCam
Replies: 4
Views: 262
Price comments in a Marketplace thread?! I'm calling for a moderator...

Er... No, that won't work...

:lol:
Forum: Digital Processing, Software, and Printing 1 Day Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Tony, many thanks - I not only don't mind the tips and advice, but greatly appreciate them. I'm also off to bed, so will respond more thoroughly tomorrow :)
Forum: Digital Processing, Software, and Printing 1 Day Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Thanks, Tony :)

I'm calibrating to D65, gamma 2.2 and 160cd/m2 for on-screen work... I'm intending to create D50 profiles using gamma 1.8 at 100cd/m2 for printing, but will have to experiment with the results of that before I settle on the right levels. I'll only rarely need to use those, as most of what I do is for on-screen viewing...
Forum: Digital Processing, Software, and Printing 1 Day Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Well, my HP ZBook 15 G5 arrived today, and the BenQ 2420PT monitor arrived yesterday. I just got round to setting everything up this evening, and I'll admit to being rather pleased based on initial impressions :)

The ZBook is lovely, and the DreamColor 4K screen really is marvellous - though not perfect, since at maximum brightness (600 nits!!) there is a little light bleed noticeable in the corners and edges, but this disappears at more realistic settings. Interesting to note that Windows 10 scaling was set to 250% (!!) by default in order to give decent sized icons, text and application windows. I haven't changed it, as it looks good to me. Nor have I installed any photo processing software, and that will be the acid test in usability for me (I suspect I have some adapting to do :o). One strange thing... The DreamColor calibration software came with factory calibrated sRGB, AdobeRGB and various other profiles, but I notice that sRGB and AdobeRGB profiles had been calibrated at 500cd/m2 luminance, which seems a strange choice :hmm:... clearly not intended for photographic use, at any rate. Anyway, I've calibrated an sRGB D65 profile at 160cd/m2 (probably too high, but it's what I've been working with thus far), and everything looks good... exactly as I'd expect, but with a much nicer looking screen than I'm used to. I'll create sRGB D50, AdobeRGB D65 and D50 at appropriate luminance settings tomorrow...

The BenQ is, if anything, even more satisfying than the ZBook. The ZBook was quite an investment for me, and by anyone's standards not an inexpensive laptop. But the BenQ monitor was, in contrast, a very inexpensive bit of kit... yet despite that, the design and build quality is great. It's really very sturdy and ergonomically pleasing to use. I might have preferred "real" buttons instead of touch sensitive ones for accessing and navigating the menus and settings, but that's a minor gripe and subjective on my part. And the display itself is *beautiful*. I haven't calibrated it yet, but using the built-in, factory-calibrated sRGB profile (again, one of several on offer for different purposes), it's indistinguishable from my ZBook's new sRGB profile - at least, to my eyes, once brightness is adjusted. I will, however, install DisplayCAL and Argyll CMS tomorrow, and - as with the zBook - create D65 and D50 profiles at appropriate luminance settings, as I'm sure in reality there are differences versus the ZBook, even if I don't notice them.

Thanks again for all the feedback and help, folks. I'll report back once I've got everything calibrated, photo processing apps installed, and tried my hand at some post-processing :)
Forum: Photographic Equipment for Sale 1 Day Ago  
For Sale: Test post - please ignore
Posted By BigMackCam
Replies: 4
Views: 262
PentaxForums.com Marketplace Listing

Item for Sale
TEST POST - PLEASE IGNORE

Asking Price
100.00 GBP

Item Location
Durham (UK)

Item Description
This is the items description.

Are you the original owner of the item being sold?
Yes

Are you selling or trading this item?
Selling

Item Condition (Key)
Used
Good

Shipping Destinations
UK Only

Shipping Charge
10

Shipping Services
Royal Mail or DPD

Accepted Payment Types
PayPal

Return Policy & Additional Details
No returns unless faulty

Please send me a private message if interested in the item!
Forum: Repairs and Warranty Service 2 Days Ago  
Right to fixing a fault under warranty?
Posted By BigMackCam
Replies: 67
Views: 1,347
I think the quoted post should be attributed to the OP rather than me, but otherwise, I concur :o
Forum: Digital Processing, Software, and Printing 2 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Thanks, Tony... I should have re-read my own thread :o :p



Excellent information, and much appreciated - many thanks again! :)
Forum: Repairs and Warranty Service 2 Days Ago  
Right to fixing a fault under warranty?
Posted By BigMackCam
Replies: 67
Views: 1,347
I'm sorry to hear that :(

Given that you're in the UK (as am I), I think you have a few of options... One is to visit the Citizen's Advice Bureau with full details of your case, and ask their advice on legal recourse. Another is to take JL (and, if you paid by credit card, your credit card provider on a joined liability basis) to small claims court for the cost of the nearest equivalent current camera, given that the warranty states it will cover such. Still another option is to approach the Financial Ombudsman Service, again with details of your case. Or, finally, decide if this is a matter of principle that you intend to see through to completion regardless of inconvenience, or if you'd prefer to accept the refund already offered, move on and strike JL from your future supplier list...

You might also consider contacting Martin Lewis of Money Saving Expert, or one of the various newspaper article writers / radio station programmes that deal with consumer affairs. If I recall, BBC Radio 4 has such a programme (it could be "You and Yours", but may be something else... I forget) and is generally successful at getting companies to see sense, if for no other reason than they don't want bad publicity :p
Forum: Digital Processing, Software, and Printing 2 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Absolutely :)



I've been lucky in that the few prints I've had done looked good - though I assume the printers did some sort of exposure adjustment on my behalf before printing, which is (I'd imagine) something you don't want if you're a professional - but for someone like me, inexperienced in having physical prints made, a benefit.



Can I ask, Tony, what you calibrate to when your target is on-screen viewing, and then for print? I'd be very interested, as there seem to be many different opinions :o



I guess I'm happy if (a) my images look good - and fairly consistent - on all of my devices, and (b) if any assessment of under / over-exposure or colour inaccuracy is due to others' lack of, or differing, calibration. So long as I know I've used a sensible calibration approach and things look good to me, I'm comfortable that others may not see my photos the same way. On that note, I'm not a prolific sharer of my photos (though I do occasionally post a few on these forums), but I do share photos with my parents and a few friends. For my parents, I've calibrated both my Dad's PC screen and my Mum and Dad's tablets so that - as close as possible - they reproduce my photos as I saw them during editing. The few friends I share photos with either use similar calibration to me, or none at all - and for that latter group, I assume a position of "moral high ground" by explaining that on my calibrated screens, all looks good :D
Forum: Digital Processing, Software, and Printing 2 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
This is the only part of your post, Tony, that I would respectfully challenge...

More and more serious hobbyist photographers are using, at the very least, software calibration with their screens. And one would hope all professionals already do :p Given that photography forums like these are used by some to share their photos with like-minded enthusiasts, is it not better to calibrate one's screens in the hope that at least some people - those who've also calibrated their screens - will see a very close reproduction of what was intended?

I remember on these very forums, a few years back, a number of my photos being described as underexposed, amongst other things. I'd been processing my photos based on my preferred screen brightness, and the result was that many folks who used a lower, more accurate brightness setting saw my photos as dark, when they looked just fine to me. That was before I started calibrating my screens. Following calibration, it ceased to be an issue (or, if it was still an issue, the problem was with the viewer's setup, not mine). It didn't, however, solve the lack of skill in my photography! :p :lol: I'm still working on that :o
Forum: Pentax SLR Lens Discussion 3 Days Ago  
Sigma DC 17-50 mm 2.8 VS Pentax 20-40 mm 2.8-4.0
Posted By BigMackCam
Replies: 10
Views: 546
I have both too, and I agree withe @clackers re the Sigma. It's outstanding across the frame, even at f/2.8, and renders well in most situations. Personally, I don't find a huge amount of "character" in its rendering, but that could be due to my preferences for older film era lenses. Technically, though, the Sigma is excellent.

The DA20-40 was, for a time, the only Limited I disliked. Mine - and several others I've read about - demonstrated significant field curvature at the long end, especially when focused on distant subjects. Some have described it as "runway-style" field curvature, and my own experience confirms that. Each side and the top and bottom of the frame will be in focus at a much closer distance than the centre. Not everyone notices this, but I find it difficult to believe that it's due to copy variation. That said, I recently started to shoot with this lens with a view to accepting, rather than rebelling against, this optical quirk... and I'm growing to like it. It's very sharp (at the points where it's in focus) and produces excellent detail. You just need to use it to its strengths...
Forum: Digital Processing, Software, and Printing 3 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
First, you install "Dispcalgui" and - if I remember correctly - "Argyll" (perhaps "Argyll-ref" too?) from the Software Manager, or direct from their source or websites if you prefer. Then, connect your colorimeter and run DisplayCAL with whatever settings you prefer, depending on your particular use case (D65, D50 etc.). I mostly use "Office & Web (D65, Gamma 2.2)" since I don't print all that often, and D65 is in widespread use. By default, the resulting .icc file will be stored in "/home//.local/share/icc/" (though you can change this path in DisplayCAL's configuration). Once the calibration is complete, DisplayCAL will give you the option of setting the current user or all users to the new display profile. Or, you can run the "Colour" app in Mint, click "Add Profile", select "Other profile", then navigate to and select the new profile you just created in DisplayCAL.

It's really that simple :)

Note that if you tend to edit images for both on-screen and print use, it's worth creating profiles for both D65 and D50 respectively. You can then select the appropriate profile as required, based on the target medium (I have a D50 profile set up for those occasions where I intend to print).

Also note that any colour-managed applications (browsers, image viewers, photo editors etc.) will need to be configured to use the OS-selected display profile if possible, or otherwise pointed directly at the profile you wish to use. This is very important, as many apps don't automatically utilise the profile that the OS is using, and some apps aren't even colour-managed (in which case, avoid those apps and use alternatives where crucial to your photography workflow).

EDIT: Having installed Argyll, instead of using DisplayCAL you could of course use the built-in colour profiling in Mint 18.3 by running the "Colour" app and clicking the "Calibrate" button with the relevant device selected. But I prefer DisplayCAL due to the configuration options available, and the wealth of resulting information following calibration.
Forum: Digital Processing, Software, and Printing 3 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Thanks, Tony :)

Sadly, the BL2420PT doesn't include hardware calibration. And, though not a wide gamut model, it's one of BenQ's "Designer" series, aimed squarely at photo / video editing, CAD/CAM, animation etc. According to BenQ's product marketing blurb:

"Covering 100% of sRGB and Rec. 709 color spaces, BL2420PT’s advanced IPS wide viewing angle technology minimizes color shift to inspire absolute design confidence. 100% sRGB color gamut accuracy adheres to industry standards in digital production, and Rec. 709 reproduces accurate resolution, frame rate, color gamut, gamma, and white point performance in high-definition video work.

Each BenQ Designer Monitor is individually factory-calibrated upon production to assure precise Delta-E and Gamma performance. Calibration results are validated against industry color standards to deliver the truest and most representative view of original content."


As a result, I'm hoping that software-level calibration (using my Colormunki Display colorimeter) will only result in minor adjustments with negligible impact on colour accuracy.

The HP ZBook 15 G5 has hardware calibration built in, so I'll be interested to see how closely matched the laptop and BenQ screens are after calibration...
Forum: Digital Processing, Software, and Printing 3 Days Ago  
Working with UHD 4K 100% AdobeRGB display - some questions
Posted By BigMackCam
Replies: 109
Views: 2,000
Currently, I'm using my 17" FHD HP laptop, low-end HP desktop with an external 23" (I think) FHD consumer-grade HP monitor (which I sometimes connect to the laptop), and a 10.1" 1280 x 800 2-in-1 tablet PC. All have been calibrated using a Colormunki Display colorimeter and Argyll CMS / DisplayCAL software, and I use those profiles both for the operating systems (Windows 10 and Linux Mint 18.3) and any colour-managed apps - web browser, image viewing and editing, etc. The external HP monitor was closest to displaying accurate colour and contrast out of the box, changing only slightly after calibration. The default profiles for the laptop screen and (to a slightly lesser extent) my 2-in-1 were very cold and unnaturally blue, and both benefited hugely from calibration.

I'll colour manage my new laptop + external monitor setup in the same way.

Of course, this only guarantees that photos will look consistent between my different screens, plus any one else viewing them on accurately-calibrated, colour-managed systems. But that's the best any of us can hope for :o
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