= black
X-
XX
= dark grey
X-
-X
= mid grey
--
X-
= light grey
--
--
= white
These can be represented by 4 numbers or 2 squared, ie 2 bit. As you can imagine, 16 bit allows many more shades to be recorded, but they can only be reproduced if the printer is high enough resolution to be able to fire enough dots per cluster to accommodate all the bits.
Actually, modern laser photocopiers seem to be able to cope with a grey input without screening - hence the experimentation to see what gives the best results.
Screening is an option tool inside Adobe Photoshop which is the professional program for photo editing. There are a number of cheaper programs which are very nearly as good, like Paint Shop Pro and Corel Photo Paint. Again, I believe both of them provide a screening tool.
From: Brian W. Dawe
When photocopying photographs in black and white on a photo copier there are some considerations: type of copier and its process (new/old liquid or dry toner & analog/digital). Different models and brands will work differently no liquid copier makes a great reproduction of photographs Older Copiers >5+ years often do not have as much "half toning" capability or gray scales many of the newer copiers have a "halftone " or "photo " mode (look on the front panel for a switch so labeled). A digital copier will do the best job as it is the latest in tech. and has almost always got the ability to handle gray scale copies.
Also available is a "Copyscreen " a mylar sheet with many white dots that you place between the exposure glass and the photo (I have used the copyscreen from Graphic Products Corporation of Wheeling Il USA )
The originals make a big difference too (not too lite/ not too dark ) but you should get to know the abilities of the copier and how it responds
Last and best but most expensive option is to have the copies made on a digital color copier (side note to this is that many if not all digital copiers can be connected to a computer and used as printers , so take in the whole works on disk or download the job to the printers server and have him do the job for you)
From: Paul Joachim
Allow another editor to contribute a little. The WLMS Newsletter is reproduced by photocopying and we have managed to get the use of private Xerox laser photocopiers that will copy double sided onto A3 which can then be folded forming a booklet. Cost in monochrome works out at about 2p per A4 sheet or 8p per double sided A3 on a run of 24 pages and 80 copies or so. Commercially the best offer we got was from Staples the office supply firm who would do a similar price on A4 (not A3) stapled once in the top corner. They use Oce copiers which are not so good if you want photographic reproduction. Once a year we do a colour edition which costs 50p per A4 page in a run of 4A4 pages x 70 odd copies. For this we use Staples' Canon colour machines.
The fun starts in trying to prepare photographs to reproduce satisfactorily. The best I have managed so far (am still experimenting) is to screen the photo at 100 lines per inch and reproduce at 1440 dpi (which accommodates a 16-bit gray scale) on an inkjet printer (Epson) on high gloss paper for the master. The copier is not very tolerant of wide dynamic range so you have to adjust the photo rather lighter and more soot & whitewash in tone than ideal.
From: Tony Brown
I use TIF for scanned line-art & half-tones but otherwise its use is very limited.
JPG works by carefully reducing similar colours down to fewer colours. It doesn't strictly speaking directly act on edges although that can be a side effect in some situations.
As a guide any of the 'Hugh Henry' modelplans I've been involved with have the original photographs scanned in at 300 dpi but optically enlarged by the scanner up to 200%. The pictures are then basically kept in JPG format (actually converted to TIF for layout as software loads them faster). All the CAD drawings are in WMF format.
For what you are doing I would suspect you could save memory by scanning at 300 dpi without losing anything much.
Scan at the best resolution you can, which is usually the largest in memory (but a file three times as big is not necessarily three times a better picture, it may only be 10% better - or not even visibly much better). Dump what you don't need or store it if you can't bear to lose it. I think the golden rule is, always start with the best image you can possibly get and work down from there.
JPG is good enough for the World Wide Web, certainly, and may be good enough for a print magazine depending on what you find acceptable.
I would probably compromise and keep TIFs for the current issue but store the archives as JPGs. If you are keeping the prints you can always scan them in again if you want a really good copy at some time in the future. There is also the likelihood that in a few years time you will have a better scanner and lots more storage as your gear gets upgraded so you might want to re-scan anyway if you were using a photo again.
Otherwise you want a good mass storage system, using flopticals or zip drives or some such. If you are serious enough to envisage collecting large numbers of publishing quality photographs, then investing in storage is part of the seriousness, whether it is cans for storing films, or electronic storage.
From: Chris Bourne
Any Computer photo/print experts out there?
Basically my scanner is up to 600dpi, my printer 600dpi. If scanning colour & B/W photographs to obtain the best B/w print - Is the TIF format the best one to use? (It takes up a lot of memory) , I am experimenting with JPG
Any tips, suggestions? All my pics are Meccano related, as I am Editor of MMG newsletters, MMGG & SAMC News but I am not to proud to ask for advice, and only wish to mprove quality of material.
From:Bob Thompson
Perhaps one of the web-hosting Spanners may care to offer some comments on the size and resolution of photographs suitable for display on websites. Here I mean physical size (e.g. xcm x ycm - or should that be inches!), how many pixels or dpi, and what size file (in kb)? Clearly one can't display a full size image (600 - 650kb) from my digital camera at 1280x1024 pixels - when viewed in Internet Explorer on my 15" monitor it is around 35cm square (It won't all fit on the screen at once)!!! The detail, however, is amazing. If anyone wants to see a full-size high-res photo, is prepared for the download costs, and has an Internet Service Provider that will allow large attachments, I'd gladly send one to you.
Last night I did some experimenting with the top-resolution images using a package called Ulead Iphoto Special Edition. It allows you to choose between poor quality (0%) and top quality (100%) on a percentage scale when saving images. I found that you can save a top quality image at 20% with a considerable saving in file size but still very acceptable quality for display onscreen. At 50% it's hard to see much image degradation at all, however at 0 - 5%, the image is best described as awful.
Also, Chris Bourne, I'd be interested in details (size, resolution etc.) of the photos you included in your Camel PDF file. Did you prepare the whole thing as a document in a word processor first?
Dr John D. Stark
Another alternative that could get you started a bit faster is to use the html editing program in I.E., FrontPage Express, it is standard part of I.E. (I think?) and it lets you prepare webpages like a word processor. Netscape as something nearly the same (from a quick glance).
I use Netscape Composxer a lot - it is powerful once you get the hang of it.
Peter Finney
There are many different graphics editing programs of varying quality out there. Some are better at some things than others. I find Corel PhotoPaint is far more accurate at converting *.bmp files to *.jpg files than any others I've used.
I use Paintshop Pro which is shareware (and hence much cheaper than Corel). To see the results look at my website at http://www.crabby.demon.co.uk.
The pictures on my website are mostly between 10K and 30K .jpg files. I find that this is a reasonable compromise between speed of loading and quality.
Physical size is of no consequence as you can scale the pictures to any convenient size. I try not to use pictures that are too big or they will not fit comfortably on the screen of the person looking at the
picture. All my pictures are photographs which are scanned using an HP flat bed scanner and then converted to .jpg using Corel PhotoPaint. Corel allows you to alter the size and resolution of the picture to suit
your needs as well as allowing you to adjust the amount of compression used in converting to a .jpg. I prepare my pictures and web pages off line and then view them using Netscape to make sure they look OK before uploading them to the server. I know that some Spanners have been concerned about the time and effort of learning to write HTML. I assure you, it is not hard to do and you can produce perfectly acceptable pages with just a few simple commands. If you look at a page you like and then hit "VIEW", "DOCUMENT SOURCE" you will see the HTML which generates that page. All of my website has been created using just a few commands. If you keep it simple it is more likely to work. I use Notepad to create the HTML. No special software is needed at all. If you see a page you like, just capture the HTML code and then adapt it to your needs.
Nigel Pope(London)
The best thing for you to experiment yourself. Save one of your photos as a *.jpg file in a folder. Find the file using Windows Explorer, and double click on it. It will automatically open up in your default Internet Browser, I suspect from comments you have made in the past you use Microsoft Internet Explorer. It will appear in exactly the same form as it would in a webpage. It will be more meaningful for you to work it out for yourself from there. Remember it will load a lot faster from your hard drive than it would download through a modem.
There are many different graphics editing programs of varying quality out there. Some are better at some things than others. I find Corel PhotoPaint is far more accurate at converting *.bmp files to *.jpg files than any others I've used.
In terms of size of images, remember a lot of people still use 14" monitors. Too often you see people lay webpages out without thinking about how they will reconfigure in different size monitors or even a reduced frame when a search engine is used. They also forget that people will be downloading from the net... you run into some awful sites (not Meccano ones!) that take ages to download because text has been produced as graphics files rather than just using standard fonts...sorry I've gone off topic. :-)
One last point. What Display settings are you using? Most computers come out of the shop with them set at 256 (8 bit) colours as default. If you have those settings, try setting them at high colour (16 bit) for a comparison. If you want to adjust your settings, double click on My Computer, Control Panel, Display and then Settings. In the color palette try the different settings. Warning do not play with the Desktop area. My neighbour did that... it messes up your font sizes!
Wes Dalefield
Don't do what I did and just buy the cheapest available - I have regretted it ever since. I am not at all happy at the picture quality (see my web site http://members.aol.com/nbrunning/ ) and I am seriously thinking about retaking the photos with a normal camera and scanning them.
Regards
Nick Brunning
The best thing for you to experiment yourself. Save one of your photos as a *.jpg file in a folder. Find the file using Windows Explorer, and double click on it. It will automatically open up in your default Internet Browser, I suspect from comments you have made in the past you use Microsoft Internet Explorer. It will appear in exactly the same form as it would in a webpage. It will be more meaningful for you to work it out for yourself from there. Remember it will load a lot faster from your hard drive than it would download through a modem.
There are many different graphics editing programs of varying quality out there. Some are better at some things than others. I find Corel PhotoPaint is far more accurate at converting *.bmp files to *.jpg files than any others I've used.
In terms of size of images, remember a lot of people still use 14" monitors. Too often you see people lay webpages out without thinking about how they will reconfigure in different size monitors or even a reduced frame when a search engine is used. They also forget that people will be downloading from the net... you run into some awful sites (not Meccano ones!) that take ages to download because text has been produced as graphics files rather than just using standard fonts...sorry I've gone off topic.
One last point. What Display settings are you using? Most computers come out of the shop with them set at 256 (8 bit) colours as default. If you have those settings, try setting them at high colour (16 bit) for a comparison. If you want to adjust your settings, double click on My Computer, Control Panel, Display and then Settings. In the color palette try the different settings. Warning do not play with the Desktop area. My neighbour did that... it messes up your font sizes!
Wes Dalefield
Yes, a flash was used. I've not used the camera enough to know about it's abilities in poor light conditions. However, when the flash has been on auto, I've been surprised sometimes that the flash has not been activated when taking some indoor (people) photos. The camera lens is f=7.6mm (said to be equivalent to 35mm on a 35mm SLR) and it autoselects either F3.2 or F8 when taking photos. The focus distance in macro mode is 3.5 inches to 1.6ft and in normal mode, 1.6ft to infinity. (I quote the imperial measurements than any Spanner can relate to). The sensitivity is equivalent to ISO 100 and the shutter speed varies automatically between 1/4 and 1/1000th of a second. If I interpret these data correctly, I'd guess that it will handle poor light about as well as an SLR loaded with 100 ASA film? Someone more versed in photography may make more sense of it. Running costs should be quite low - it uses 4AA cells and NiCds are recommended. Can also have a 5V DC input from a transformer. Some digital cameras use quite expensive non-rechargeable cells.
Yes Chris (Bourne), one of my main intentions is to use the camera to photograph Meccano models and to produce building instructions using a combination of ISOMEC and photos to illustrate them. I still plan to progress the instructions for my Arnfield grandmother clock. I started on ISOMEC (I completed the most complicated bit - the epicyclic winding drum) but found it rather time consuming. I figure than photos are easily the most efficient way of documenting the less complicated bits. Your "Camel on the web" is the kind of thing I'd like to do - it's all a matter of getting the time. I have the full version of Adobe Acrobat so should be able to produce PDF files (although I have not tried to do so yet).
Melvyn, you are correct. Christmas does not come 3 days earlier in NZ than in other countries - a few hours perhaps. I don't quite know how I got away with not having to wrap it all up and put it under the tree. Perhaps it's because there'll be no Meccano in my Christmas stocking this year
Dr John D. Stark
I have recently purchased a digital camera as a Christmas present to myself with my wife's blessing too as she'd been looking unsuccessfully for a particular gift for me (I don't know what!) and could not find one (whatever it was). Of course the camera was much more expensive than what she had in mind!!
The camera is a Fujifilm MX500 (which basically is the same as the MX700 except the latter is more expensive and has a smaller alloy case instead of the slightly larger plastic one). The feature that appealed to me was the maximum resolution of 1280x1024 in a camera costing just over $NZ1000. (I see on the 'net than US prices are even cheaper at US$402 - $480). No other digital camera available locally has such high resolution on the low side of $1500. It has a macro facility and a 2X digital zoom (not necessary) but no optical zoom. I'm extremely pleased with it's performance and have photographed a number of Meccano models with excellent results. They look superb on a computer screen and print out very nicely on my Epson Stylus Color 400 printer. I have attached a very small fragment of an image from the top of my Arnfield Mantel Clock to this email. This image is at the highest quality that the camera can produce, so I've attached only a very small part (13kb) from the entire image (648kb) to keep (hopefully)within the email size limit imposed by the Spanner list. Full size high resolution images take up 600-650kb of disk space.
The standard camera only has a 2Mb Smart Media card, which can hold only 2 images at the highest resolution or 39 images at the lowest resolution (and various numbers in between depending on the combinations of image size (1280x1024 or 640x480 pixels) and quality mode (fine, normal, basic). The quality mode is effectively the compression ratio (1/4, 1/8, or 1/16) of the JPG files created by the camera. I've ordered a 16Mb Smart Media card ($NZ190) that will store 24 images at the highest resoultion or up to 322 images at the lowest.
In comparing the 1208x1024 and 640x480 modes for photographing Meccano models, I'd say that the former is a must in order to retain the detail so that images can be printed out at a resonable size. I'd even suggest that the highest quality images would be good enough for CQ (although not quite up to the standard possible with conventional photography). A full size 1280x1024 pixel image is actually too large to print on an A4 page on my Epson 400, so needs to be scaled down to fit on a page.
I should add that I do not have shares in Fujifilm and will gain no benefit whatsoever if you all rush out and buy an MX500. However, if you're after a digital camera with excellent performance for the price, I doubt that you'd find anything better at the moment. Tomorrow, of course, it will all be different!
Cheers
John Stark
| return to previous page |