Artwork creation problems
How to make negative artwork
You can use the artwork program of your choice such as Corel or Photoshop or free to use programs such as Photoscape or Gimp. You need to invert the image into a negative by doing the following easy steps:
- Convert the image to a grayscale (you can ignore this if it is already greyscale or black and white).
- Optimize the brightness and contrast. This is to make the blacks strongly black and whites strongly white. If you don’t do this the file can still be converted to black and white, but you may lose some detail.
- Convert to black and white. This is called bitmapping and makes the file 1 bit.
- Invert the blacks and whites to make a negative.
Artwork is the wrong size
This is an issue with your software. When you have your artwork at the correct size you can send that file to your printer and it will print it at the size determined by your image on your screen and this will be the exact size of your stamp.
If you are using Word you can fix the size by fixing the size of the text box you are typing in.
If you are using an artwork package it will provide the opportunity to re-size an image by either clicking on it and entering the correct dimensions numerically or just by pushing or pulling at a corner.
It is worth clicking print preview before printing just to check that the size looks correct.
Negative making problems
Which printer to buy
All inkjet printers will make a negative, but only some laser printers will print dark enough. If you want a low cost option we would recommend the HP 1050, 2540 or 3055 PSC (Printer/Copier/Scanner) so you can use it to scan and upload drawings as well. Even the lowest cost printers will print dark negatives straight from the printer. Almost all inkjets can print negatives dark enough to use, but you will have to optimize the print settings.
Getting your printer to print black
Negatives have to be black enough to stop light where you don’t want it, whilst at the same time be clear enough to let light through and have the correct resolution to deliver your desired image.
We recommend you use an inkjet printer. Nearly all inkjet printers will print dark black enough to use as a negative, but you will have to select the optimized printer setting.
- Ensure the file you are sending to your printer is black and white, not color or grayscale.
- Use our imageblack inkjet film and print on the coated side that sticks to a damp finger. Do not use standard OHP
- Find the optimized print setting by printing a small black box using different print settings and look at it against a light- use the darkest black one. You could try all the settings from the shortcut menu (typically ‘specialty printing’ or ‘presentation printing’ work best) or change the paper type to ‘matte’ or ‘photo paper matte’
If available also increase the ink volume.
We recommend any HP inkjet, the basic PSCs (printer copier scanner) type in any range work well.
Your inkjet negative is still wet
There are two reasons for this, you have either inserted the film in the printer the wrong way round and are printing on the uncoated side, or you are trying to deliver too much ink for the film to absorb.
Always print on the side that will stick to a damp finger, this is less shiny and slightly rougher, the other side is completely non-absorbent.
In the rare case that you have selected a print setting that is dropping down so much ink that the film is just over-loaded, select a less ink heavy print option, select a less absorbent paper or reduce the ink volume, but do still check the black stops light.
Using laser printers
Not all laser printers will print black enough. We recommend the HP brand. If you have the option you should increase the toner density, this is obtainable via the Start menu, then access the control panel and in ‘Properties’ of your laser printer remove toner saver or increase the density. You should use our imageblack laser film as it is optimized to be receptive to toner. You will have to darken the printed film with solvent, the easiest way is to buy an aerosol of toner density spray, but some printer types can be wiped with white spirit (turpentine) and heated with a hot air gun to turn the grey toner jet black.
You have a solid stamp
There are two possible causes: either your negative is letting light though (which is the most likely one) or you have made it incorrectly. In all probability the cause is that your negative is letting light through, so we suggest you look at this first.
- Negative problem– there are three simple checks to find out where your problem lies:
- Make sure that you sent a Black and White file to your printer instead of a grayscale or color file. Printing is a binary process, it will either drop ink down or not, it prints gray by printing small black dots surrounded by white. So selecting black is always the darkest.
Summary- Make sure your artwork is a black and white file, not grayscale or colour.
- Use a printer setting that delivers maximum ink. Printers offer many different settings from economy to photo quality. The darker the black, the more light it will stop and the better your stamp. Select an absorbent paper setting like ‘photo paper matte’ or ‘matte’ to deliver the most ink. If you have a shortcut menu one of those options will be the darkest black, to find which it is print a small black box using each of them in turn and look at them against a light to find the darkest black. If possible increase the ink volume. For more information on this visit http://www.photocentric.co/PRINTERSETTING.asp
Summary- Choose the darkest print setting delivering most ink, typically change the paper to ‘matte’ setting.
- Always black-off the area around small negatives. Use the template supplied if you are
making an A8 (small) sachet, or surround a small negative with card or anything that will stop light to cover the base of the clamp.
Summary- Ensure that the entire area of the base of the clamp is covered with negative or card.
The film supplied only works with inkjet printers, not laser. Do not use OHP film, the imageblack film supplied is optimized to print dark black. You can always print dark black directly, printing the same film twice to darken may give you alignment issues and if you stick two negatives together you will have to increase the second exposure time by 100 secs.
- Process error– this is the least likely cause, but there are three possibilities
- You didn’t assemble the sachet the right way round, the soft side should be next to the negative with ‘imagepac’ readable from
- You inserted the clamp with the imagepac up for longer than the recommended times. Make sure that on the vital first exposure with the imagepac open to the light, it is only in the stampmaker unit for a maximum of 6 seconds for the red 1.9mm sachets or 15 for the clear 2.55mm
- You let the imagepac be exposed to sunlight or left it close to the UV unit before you washed away the
You have a liquid stamp
This is the easiest problem of all to correct – the cause of the problem is too little light reaching the imagepac sachet.
Make sure your stampmaker light unit is warmed up before use, do this by turning it on for 1 minute before inserting the clamp.
If you are using two negatives or you have printed your negative on vellum (opaque or frosty) film you will need to increase the second time by 100 secs.
Not enough detail to your stamp
If you have lost detail, it is either because you didn’t have the detail on your negative or you didn’t make the stamp properly.
No detail on the negative
This is either because the file was grayscale and not black and white or because your negative was not black enough. You can check whether the file was one bit black and white by checking the properties of the file on the screen. If you expand the image size in an artwork program to the pixels you will either see black & white squares or greyscale ones, alternatively, just save the file as a black and white file (called bit-mapping). To check whether the artwork is dark black look at the negative against a light, if you can see through the black parts then it isn’t dark enough.
You lost the detail in the stamp making
This is because you either over-exposed the stamp or didn’t wash it out properly. Over-exposure means that you have shone too much light for the second exposure. Reverses (such as the centres of ‘e’s) fill in and lines become bolder when this time is too long. For artwork with a lot of clear areas on it and small areas of black, you should reduce the second time by approx.20 seconds. It’s very easy to wash stamps properly, use lots of running hot water, detergent and brush vigorously; if your stamp is made properly it will not be damaged by the washing.
Level of detail you can hold
The detail of the stamp is a function of two things, the quality of your negative and the optimization of your second exposure time.
So set your printer to print on max dpi, with inkjet printers this should be 1200dpi at the minimum. Make sure your file is created at a minimum of 300dpi, ideally 600dpi. To hold the finest of text you should use a second exposure that just makes the fine lines strong, but doesn’t widen it. With stampmaker 1.9mm (red) using a first time of 6 seconds, the minimum second time is 60 seconds, although 100 seconds is safer. If you reduce the second time the text will be finer, this is easier to do with a higher floor, which means a longer first time and the longest you can leave it in is 10 secs.
Stampmaker will comfortably make 4 point text, if the negative holds it.
Stamp is still sticky
Sometimes your stamp can be still sticky, it varies according to the type of water used and the amount of light. Make sure the stamp is thoroughly dry before testing how dry the surface is.
The simplest way to get your stamp surface really dry is just to extend the time under water under lights, you can leave it there for as long as you want with no ill- effects, but bear in mind it will absorb water so will need drying for longer. 6 minutes should be long enough to get any stamp dry.
You can adjust the water to make it reduce the stickiness on the surface by pouring a little washing up liquid (or dish soap) into the post exposure water tray.
If you really don’t have the final dryness you need, you can dry the stamp thoroughly before placing it under the water for final hardening, this will also make it shinier. You will also find that you can do the final hardening surprisingly effectively using sunlight.
You can’t peel the back off the imagepac
Stampmaker 1.9mm (red) has sachets with a rigid back that is always attached to your stamp, you cannot remove it. Use imagetac cling to attach your stamp to your mount. 2.55mm clear imagepac sachets have a removable back.