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dan_lee16

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Posts posted by dan_lee16

    Superfine grain film developer

    in Black & White Practice

    Posted

    <p>Logically I would think to regenerate oxidised quercetin back again, eg; reduce it back to it's state, it would need a more powerful reducing agent than itself, hence I don't think ascorbate would do that.<br>

    And salicylic acid under goes the acid base reaction to form salicylate :) Aspirin hydrolyses to salicylic acid in strong acids.. however it will also hydrolyse straight to salicylate in a base, so there's an easy source there.</p>

    <p>Murray: I think you can get it in some health supplements. I've seen it on ebay in 500mg tablets.<br>

    I guess one could mash onions into water, boil it (another something I read states it doesn't damage/decompose etc at cooking temperatures) and vacuum filter it to wash out all the water soluble compounds, then mix whats left with a base, filter that, titrate the base to neutral pH.. hopefully the quercetin should precipitate out if there's enough of it.</p>

     

    Superfine grain film developer

    in Black & White Practice

    Posted

    <p>It actually has interactions with Vitamin C, it may even be super-additive with it - the other way round to normal, this compound may regenerate Vitamin C. The amount of this compound in certain organic matter is far higher than the range of polyphenols found in most things.</p>

    <p>The chemical structure has numerous hydroxy groups on rings.. it appears like a powerful developing agent.</p>

    <p>The solubility is low in most solvents, water, ethanol, even DMSO I think, not sure about TEA and glycol. But it has high solubility in bases iirc.<br>

    The data that I -can- find, suggests 50g/L of the compound is soluble in 1M of NaOH (39.997g/L NaOH)</p>

    Velvia 100 @ EI 6, 3 min in E-6, or C-41 cross?

    in The Wet Darkroom: Film, Paper & Chemistry

    Posted

    <p>Hey,<br /> <br /> So I've got a 120 roll of Velvia 100 sitting here, which I am fairly sure is from my days at uni last year when I went up in the helicopter.<br /> <br /> Also had a shot a roll of Ektar 100 that say dame.<br /> <br /> The lens was stuck at 1/15th for any speeds faster than 1/15th, and I had it set at 1/250th, so that's +4 stops of overexposure, the Ektar still came out, that was already processed, I wondered why it was so dense, then remembered that I later found out the shutter speeds weren't working properly on that lens.<br /> <br /> <br /> I have both my own Kodak Flexicolor C-41 and Kodak E-6 chems.<br /> <br /> So I can run any time in either of these.<br /> <br /> Should I process say 3 minutes in E-6 for first dev?<br /> <br /> Or run it through standard C-41? Or shorter time C-41?<br /> <br /> I've run film through C-41 @ 2 minutes without problems, so I wouldnt hesitate to run a 2 minute time if need be to keep the film from getting too dense.<br>

    What I want is good density from it.</p>

    Why is VueScan -still- so crap? (terrible neg clipping)

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    <p>I'm not new to VueScan, I never had this problem with a Dual Scan II setting it up for someone else, in 2008 on a much older version of VueScan.<br /><br />My scanner is also not faulty, other than being a flat bed with a terrible SNR, poor optics and scan artefacts, it is consistent without problems.<br /><br /><br />Alan, Steve, I'm not stupid, please read the OP, the software is clipping the values before other settings are applied. In VueScan only.<br /><br />Indraneel, I don't have trouble in any other software with clipping or colour. <br /><br />Edward: VueScan <strong>IS</strong> clipping it. I am not using the wrong settings. I would call using Internegative as the wrong settings.. but I still have to use it, I've even used the none setting for no-correction in VueScan and opened up every value, and tried every which combination, as pointed out earlier, only the Kodak Internegative profile actually helped, every other single control is being applied post-clipping, and the only way to prevent that clipping occurring beforehand is to switch to the Kodak Internegative profile it appears.<br /><br />As I said, that is a band-aid approach, a dedicated scanning package should let you colour correct and use the correct profile without clipping. In fact a dedicated scanning package should make those variables transparent and available to the user.<br /><br />RGB exposure/scanner exposure isn't an issue, it isn't putting up a value too high that is clipping the base/mask, so it also isn't clipping the shadows during scanning (and I also know that again because of the Kodak Internegative profile option), it's being clipped internally by VueScan before anything else comes into play (again, I can see this by switching to Kodak Internegative profile without needing to re-scan, the data is there for the shadows, but it gets thrown out, some of it is higher density than other negatives which don't have it thrown out it appears, it depends on the rest of the frame - even with all adjustments off - if you're not in Kodak Internegative, nothing brings it back).<br /><br /><br /><strong>Zack</strong>: It is correctly exposed for the scan, as I said the detail is there, I don't mind having to make flat results beforehand, but both in Epson Scan and SilverFast, the detail is well exposed that I do not need to make flat results, the detail is dense enough to be in there in a regular contrasty picture straight off the bat.<br /><br />I too use Rodinal - though I've had a stand-developed negative reach from just about 0 dMin to full dMax (Shanghai GP3), so I wouldn't say it's ideal for scanners, it depends on a lot of variables, I could still deal with that fine and squeeze in the detail I wanted.<br /><br />I'm not confused about the exposure difference for an enlarger and a scanner. Please do not make assumptions. <br /><br /><strong>Scott</strong>: Setting colour balance to none doesn't help the issue, none of the tools change any amount of the clipping which suggest they are all applied post-clipping, which is verified since nothing brings the detail back, but the Kodak Internegative profile does (with sharpening off), appears that there is a variable level of clipping that VueScan decides on a frame by frame calculation, there is no control to alter this, the only thing that did help was switching to the Kodak Internegative profile.<br /><br />Someone would complain that commercial software doesn't work how it's supposed to you, and you have to use a band-aid approach and forego one of it's major features? Right.<br /><br /><strong>Chris</strong>: Read my posts. Locking the exposure doesn't make a difference, it doesn't make a difference if I even set manual exposure and lock it on either extreme end, it still decides to clip that area, unless I use the Kodak Internegative profile as pointed out by another user. <br /><br />I don't have a trouble getting good colour, or dialling it manually. The point is I can't do that, because I have to switch to the Kodak Internegative profile.<br /><br /><br /><br /><br />I decided unless it was significantly important part of the image, since I'm only using a V500 (that I'd pay for high end scans for anything I want for archival or gallery etc), I would just forget about it, and concentrate on just finishing the colour to a nice standard, since I like the multipass scanning as I've said, the dust removal is better, and I can get great colour (on the preview) much faster than I can correcting in Photoshop.<br /><br />I'd consider SilverFast, if I could find the infrared cleaning, the SRD option when scanning only appears to do the software clean without IR mask. But I'm only using the demo version.<br /><br /></p>

     

    Why is VueScan -still- so crap? (terrible neg clipping)

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    I'm on 9.0.18 as noted in the opening post, which is the current version.

     

    Yep, except when in VueScan using the tools to try and compensate for clipping makes ridiculously flat scans, while still clipping. There's a hard cut in the software.

     

    AS opposed to in Epson Scan, where this detail is actually there, without expanding the levels to a flat contrast, IE: it's not a huge contrast range of detail that I'm scanning, it's deciding to clip regular detail, in Epson Scan, detail is there, while being contrasty, I can expand the levels for a flat picture, but there is no more data, just empty histograms space, both dMin to dMax was contained in the smaller histogram area, expanding it more is a waste of bit space in the file.

     

    None of the profiles or settings or exposure work against clipping because they apply post-cliping. Except the internegative profile as one user pointed out, software there is still some loss on the "severe" negatives (the negs are great themselves, no messing around in epson scan to see the detail, its not clipped while still being contrasty.

     

     

    The interneg profile however is working (it appears) for less "severe" negatives (ones where the clipping in vuescan is of smaller contiguous area rather than larger).

     

     

    This is a band-aid approach and prevents you from using colour correction or the colour profile of your film, VueScan has been around for a long time... this really isn't acceptable.

     

     

    However turn sharpening on with the interneg profile... it changes the colour.. and goes back to clipping... changes the colour on all profiles by the look too.. sharpening shouldn't do that.. that is really broken and unfunctional.

     

    Software thats being sold thats been around for so long should at least function and have it's basic functions actually working.

     

    This is a dedicated film scanning program and doesn't let you even control where the clipping cut-off occurs for all those other profiles either. Disgraceful.

     

     

    Well, the software still works a lot better than Epson scanners do at being film scanners :/ probably time to invest more $

     

     

     

    At least on the plus side the IR dust removal in VueScan is the best I've seen, it's not all bad, I haven't tried that Silverfast HDRi stuff.. I don't think it's quite appropriate to have to buy a second program and transfer into that after to do your dust removal for film scans though.

    Why is VueScan -still- so crap? (terrible neg clipping)

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    <p>Currently scanning with Silverfast demo.. it looks perfect. Profiles actually seem to be right too. Except infrared dust cleaning dosnt seem to be there....</p>

    <p>I'll have another look after this is finished, I've the 'none' (which is supposed to include everyhing), manual and various profiles.</p>

    <p>Just looked... doesnt -say- its clipped black.. but it still looks like an area of flat colour.. green now instead of flat black, though after importing a scan does seem to be more detail than before, just not all of it, I think. Well it'll have to do for now anyway.</p>

    <p>Silverfast seems only to have SRD not iSRD for my scanner.. or maybe thats the demo.. wow. Or perhaps I'm missing something. Going to call it a night.</p>

    Why is VueScan -still- so crap? (terrible neg clipping)

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    <p>Edward: Epson scan doesn't clip it. I dont even need to expand the levels, because everything on the neg is in the usual place.</p>

    <p>Mendel: I've gone through everything, nothing has an effect on the clipping. Repeat, nothing. I even scanned as a positive at various exposure lock settings and correction settings (includin"none"), and it's still actually clipped once I get it into photoshop and look at properly.</p>

    <p>Clipping is a deal breaker. You should be able to set your own cut off points anyway.. this program has been out long enough..</p>

    <p>The only reason I want to use VueScan is for A) Multi-pass scanning (awesome for a scanner like V500 that has horrid SNR) and B) The IR-dust removal, it does very well for itself, still leaves artefacts, not so bad though like Epson Scan does.</p>

    <p>All I want is reasonable 120 scans to display, given the difference between single and multipass results, noise but not grain has been an issue, any excellent images I can pay to have done on a Imacon. I'm going to try the SilverFast demo.</p>

    <p>I could use Epson Scan to scan a few times to files, then chuck those into a photoshop stack..really going to the effort though :/</p>

    Why is VueScan -still- so crap? (terrible neg clipping)

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    <p>On a V500 here, and VueScan x32 9.0.18<br>

    VueScan is often clipping the shadows and both the shadows and highlights.</p>

    <p>Eg, I got some Pro 400H in front of me.</p>

    <p>Model has black hair, all contrast and detail in the hair is gone, clipped. Does not matter what settings I use in VueScan, even with no colour balance, and locked to minimum exposure.</p>

    <p>This isn't a problem with the film. The detail is on the film just fine.</p>

    <p>It also isn't a problem with the scanner density.</p>

    <p>If I preview it in Epson Scan, I dont even have to expand the levels, the detail is there - quite comfortably in the preview.</p>

    <p>VueScan is clipping it, and I can't do a single thing about it, gone through everything. It's not even that thin if Epson Scan is picking it up without having to expand the levels.</p>

    <p>Previewing each, R, G, B channel on the colour tab shows every single channel is flat black in her hair. Happens to highlights ocassionally as well.. ones that Epson Scan pick up comfortably with expanding the density range too far.</p>

    <p>Colour correction is shockingly bad.</p>

    <p>If Epson Scan had multipas-scanning to get rid of a lot o the noise for editing and for thin-ranged and also dense negs, and IR-dust removal as good as Epson Scan I wouldn't bother trying anything else.</p>

    <p>The RAW histogram doesnt appear to show any clipping.. what gives.. if I change the type to slide.. there appears to be detail there.. let me say my negs are completely normal :/.. never the less I should be able to decide where the clipping is.</p>

    <p>But this is a real deal breaker :(</p>

    Flexicolor Replenishment Question

    in The Wet Darkroom: Film, Paper & Chemistry

    Posted

    <p>I know what the starter has in it and does, I had to make m own starter from scratch looking at varying MSDS and trial and error, till I finally go to a formula that gives great results. I've got some starter on back-order, but until then I'll stick to just replenishing (hopefully) correctly so that it will balance and remove errors from the starter I mixed, though it was already pretty good anyway.</p>

    <p>"Adding replenisher always assumes you are maintaining the original volume." -- That's all I wanted to know, thank you :)</p>

    <p><em>'Normal procedure is remove some, add the 200ml then add back some of what you just removed to bring the volume back to "normal". Usually the carryout volume is less than the amount of replenisher you need to add</em>.<em>'</em></p>

    <p>That didn't really give that answer, as it says the net result is removal of less then 200mL when adding 200mL of replenisher.</p>

    <p>So I stick to Z-131 amounts, which gives x, and remove the x amount of seasoned developer then add x amount of replenisher.</p>

    <p><em>'If you keep adding replenisher without removing any of the used dev, you end up with a larger volume of unbalanced high salts content developer.'</em></p>

    <p>If I kept adding replenisher without removing any without adjusting the amounts given by Z-131, then it would end up underreplenished. Which is what I did last time I replenished a 3 days ago but now I can account for that and adjust for it since I've kept records :)<em><br /></em><br /> IE: I need to replenish say 200mL out of 1L according to Z-131, then that is diluting the salts as you say by 20%. IE: The salt concentration build up from processing the film is lowered to 80% of what it was for this example. Then I could say I just need to add 250mL of replenisher without removing anything to achieve the same mg/mL of salts.<br>

    edit: And since my container is not full, I'll do it like that till it is to minimise air in the bottle, then I can go on to maintaining volume.</p>

     

    Flexicolor Replenishment Question

    in The Wet Darkroom: Film, Paper & Chemistry

    Posted

    <p>The amounts I add are in fractions of a mL to make up for carryover which I have calculated as I pre-soak (eg with 49.83mL of carryover of water, I might add 3.8mL of A, 0.658mL of B, 0.658mL of C), Kodak specifies an order as the developer preservative is in part B, as well mixing the concentrates together without dilution creates unwanted reactions.</p>

    <p>Developer minus starter, or rather minus conditioning from being used is replenisher, subtract the conditioning (either from starter or processing with it) then it is replenisher, add conditioning to replenisher (eg starter) it is seasoned developer, the point is they are the same dilution.</p>

    <p>If you have room in your container for greater volume, then you would not be tossing it down the sink. So that reasoning does not make sense on that level as well as on a more important level.</p>

    <p>The amount of replenisher needed is different for adding to developer, as opposed to removing the same amount of developer that replenisher is required (remove 200mL developer, add 200mL replenisher) is different, because given the same amounts for both.. one may be underreplenished, or the other may be overreplenished.</p>

    <p>I guess I should ring Kodak and ask.</p>

    <p>Do the replenishment amounts in Z-131 refer to adding that amount straight to developer? Or removing the same amount of developer first?<br>

    There can only be one definitive answer to that, as the wrong choice will lead to either overreplenishment or underreplenishment.</p>

     

    Flexicolor Replenishment Question

    in The Wet Darkroom: Film, Paper & Chemistry

    Posted

    <p>Do you have any source for that? It seems counter-intuitive since the developer is the same dilution/strength as replenisher.</p>

    <p>The replenisher is like this:<br>

    700ml H2O<br />76.3mL A<br />13.2mL B<br />13.2mL C<br />water to 1L<br>

    Developer is the same.. just with starter added and no extra water.. so replenisher is the same dilution as developer (sans starter) iirc.<br>

    Z-131 gives the carryover amounts and I can adjust for those by keeping track of what I process.. either by making a stronger replenisher, or much easier, by adding very small parts of A, B, C directly to the developer with no extra water to bring it back up to '100%', which is not a problem as I have done this before (I have a pipette small enough to measure 0.02mL amounts)</p>

    <p> </p>

    Flexicolor Replenishment Question

    in The Wet Darkroom: Film, Paper & Chemistry

    Posted

    <p>So if I need to replenish 200mL given the amounts for specific films by Z-131 manual.</p>

    <p>Do I throw away/remove 200mL from the developer then add 200mL of replenisher or just add the 200mL (then tip out some if I need to maintain a constant volume for x container size).</p>

    <p>I've just been adding the replenisher, and not removing anything prior... just wanting to make sure I'm doing it right.</p>

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