See the advanced section for more detailed information on these topics.

---

Resolution and size:

The PPI setting makes no difference, 72ppi or 1200ppi are all the same. What makes a difference is the number of pixels in the image. We recommend at least 1200 x 1800 pixels.

 

For most purposes, such as art show submission, if the image looks good on your monitor when viewed at 100% it will be fine for a 35mm slide. For publication or portfolio a larger image would be suggested. (See the advanced section for more information on resolution and high resolution imaging.) The file size (in Mb) is not critical. We have no maximum limit on what you can send.

---

Cropping:

By default your image will be rotated if necessary to produce the largest image on the film and scaled so that nothing is cut off by the mount. If the image does not fill the frame, the extra space outside your image will be black by default. If you want the image to fill the live area you will need to crop the image to to a 2:3 aspect ratio (4x6, 6x9 8x12 are all a 2:3 ratio).

---

Color balance:

Our film recorders are balanced to a standard neutral balance. Your files should be in either Adobe 1998, or sRGB color space for best match. (If you don't know what this means, then you probably don't need to worry about it.)

---

Formats:

We recommend sending files in JPEG format, saved at high quality settings. At the same pixel size there would be no visible difference in a slide made from a jpeg file or a tiff file. Altho we recommend JPEG, we can image film form TIFF, PSD, BMP, TGA, PDF, PowerPoint etc. A more complete list can be found on our Format page.

 

Your files need to be in 8-bit RGB or Grayscale. (Again, if you don't know what this means, then you probably don't need to worry about it.)

---

Copyright:

We are committed to protecting copyrights. Each customer is required by US law to own the right, or obtain permission, to use any image before the image is uploaded for imaging at Gamma Tech.

• Back to top

Why Gamma Tech makes a difference:

Send your files to us by any of these easy methods:

	Send files on line.   With this easy and secure 1 page upload form you can send up to 24 files, select shipping and payment options and hit the upload button. If you have more than 24 files you can either upload more than one set and have them all shipped together, or you can use our built in FTP interface and upload any number of files.
	Built in FTP.   Our FTP (File Transfer Protocol) interface opens in your browser, no extra software needed. Select files or folders, start the transfer and fill out the order form while your files upload. This is a great option if you have lots of files, or just some very large ones. Once the transfer completes you can see your files on the server to be sure everything arrived.
	Mail your files, prints or negatives.   Fill out this easy form and hit the print button. Send the form with your files to us for imaging. You can send digital files, negatives, or prints up to 8x10 inches.
	Use our printing interface.   Slides are available as an option with our printing interface. Files should be in jpeg format, and credit card or Pay Pal payment will be processed by Pay Pal.

• Back to top

---

Film Recording:

We use the highest quality film recorders to produce your digital slides. The diagram to the right demonstrates the basic concept of film recorder operation.

 

A film recorder consists of an extremely high resolution monochrome CRT, cut-off filters, shutter and a lens/camera option.

 

The file is sent to the recorder one channel at a time: Red, Green, then Blue. If you were to look at the Film Recorder CRT during an exposure, you would see a bright spot of light scanning each line of the image, working it's way from top to bottom.

 

The exposure takes from 30 to 90 seconds for 35mm, and up to 15 minutes for a full resolution 16k 4x5 or 8x10 exposure.

 

For each image channel a corresponding cut-off filter rotates into the light path. This results in Red, Green and Blue exposures on the same piece of film to form a complete image.

 

When all 3 colors have been exposed the image is complete and the film can be processed.

 

All 35mm digital slides are imaged at 4k resolution (meaning 4,096 pixels in the long dimension) using Agfa Alto 16k film recorders.

 

Our calibration methods for this process are unmatched. If you send us a grayscale image you will get back a slide with no color bias - GURANTEED!

 

Compare our quality to other services at www.slidesurvey.com!

 

Agfa Alto with 35mm bulk option.	Agfa Altos with 35mm bulk and 8x10 film options.

---

Film Processing:

 

Even the best film recording is garbage without great film processing. In the past 30 years I've operated several E6 labs, and Gamma Tech has run film at 4 labs in the past 15 years. Our film is now processed by (in my opinion) the best E6 lab in the country.

 

Digi-Graphics, located in Ft. Collins Colorado has recently upgraded their facility, and installed new equipment for film processing. At right is a photo of their newly installed Refrema E6 150 GL-Custom film processor, which provides accurate and consistent processing from 35mm to 8x10 sheet film.

 

Mounting, sleeving, final inspection, packaging and shipping of orders is done at Digi-Graphics by a team of highly qualified technicians with over 60 years of combined experience.

 

Digital slides are shipped within 24 hours (excluding weekends and holidays) in plastic mounts and sleeved in archival plastic pages. (Sorry - Cardboard mounts are not available.)

 

We stand behind our work 100%. If you are not happy for any reason with the quality of the recorded image we will either re shoot the film at no charge or we will refund the full amount of your order.

 

---

Image file size and resolution:

Image resolution is not important in film recording, only the number of pixels in the image. Having said that, here are some basics about resolution that may help you understand image sizing.

 

Resampling an image: This option will either remove data from the image to make it have less pixels, or insert data into the image to make it have more pixels. In either case the quality of the image is changed by resampling. If your image is 1000 pixels wide and you resample it to 500 pixels, 1 of every 2 pixels in each dimension will be deleted to make the new image. If you resample from 1000 up to 2000 pixels the software will add intermediate lines in each dimension based on the original image, and give you a new image 2000 pixels wide. In either case, the quality will be affected by resampling, which is why we don't recommend resampling your images before sending them to us.

 

Resizing an image: This option will only change a bit of code in the file, which will be read by some output device (such as a printer) to determine how many pixels to use for each inch printed. If you have an image that is 1000 pixels wide, and the file resolution is set at 100 pixels per inch, a print from the file will be (1000 pixels/100 pixels per inch) = 10 inches. If you change the resolution to 500 pixels per inch, the resulting print will be (1000 pixels/500 pixels per inch) = 2 inches. In both cases the image is unchanged, only the data in the file header has been altered.

 

All film recorders are based on fixed sizes (35mm, 120, 4x5 etc). Resolution in the file header is not used and the image is interpolated by hardware to the appropriate size for the film being recorded. Some companies use this as an advertising point, saying that your files are exposed at exactly 1:1 with no resampling, giving you the sharpest image possible. The fact is that any company using film recorders is doing exactly the same thing, that's just the way it works, and the hardware interpolation is much better than a resampled image because the film recorder hardware is customized to produce the optimal result with that particular film recorder.

 

For good quality 35mm slides we recommend files 1800x1200 pixels or larger. Smaller files can be acceptable if there is not much fine detail in the image. Smaller pixel size images will appear less sharp on film.

 

A chart of recorder resolutions is given below. Full frame 35mm slides are 4096x2732 pixels, also called 4K. We can image at higher (or lower) resolutions, but 4K is optimal for 35mm film. 16K is optimal for 4x5 film, but often 8K is used since there is no quality gain if the original file is smaller than 8k resolution.

 

35mm Film Recorder Resolutions
Resolution	Horizontal Pixels	Vertical pixels	Pixels/Inch	Raw file size
4K	4,096	2,732	2,872	32.8Mb (11.2M pixels)*
4 x 5 and 8 x 10 inch film:
8K	8,192	6,144	1,795 / 881	147.5Mb (50M pixels)*
16K	16,384	12,288	3,590 / 1,762	589.8Mb (200M pixels)*
*Digital cameras require approximately 3-4x the Mega pixel numbers of film to produce equal resolution since each pixel on film can be any of 16 million colors, while digital cameras require several CCD red, green, and blue cells to produce one pixel of color.

 

---

Borders and Rotation:

Images that are not in 2:3 aspect ratio are scaled to fit the 35mm frame with no cropping. The space outside the image will be black by default. If you need some color different than black you will need to add it.

 

We view the image being recorded as horizontal (Landscape). We rotate vertical (Portrait) images 90 degrees to give the largest possible image on the film. If you want a vertical image centered in the horizontal frame with black on the sides you will need to let us know when you place the order.

 

Here's a reference chart to help visualize the 2 above:

 

What you need:	Your file:	The film:	Mounted slide:
Full frame horizontal slide
Full frame vertical slide
No crop from less than full frame image
Vertical image
Vertical image on horizontal slide

---

 

 

 

 

Crop?

We resize and add borders to images so that the image is not cut off in the mount. The aperture of the plastic mount is (approximately) 3840x2560 pixels, and does vary slightly depending on the lot number of the mounts. If you need mounted slides with no scaling we would recommend sizing your files to 3840x2560 or 4096x2732 for full frame digital slides.

 

---

Color Balance?

Our process is balanced to produce the most accurate color possible on transparency film. Film can produce a much wider range of colors than a computer monitor, so comparing the slide to a monitor is difficult. Here's a very simple way to judge your monitor color, density and contrast without spending hundreds or thousands of dollars on software and calibration devices. The scale below is a 16-step gray scale. First of all, it should look gray. You should also be able to see differences in the steps indicated. Steps 15 and 16 are difficult to see on any monitor, but you should at least see a difference from 14 to 15, and some LCD monitors may have trouble with the brighter steps. If this scale looks good on your monitor, and your files look good on your monitor, then you will be very pleased with your ditital slides.

 

 

---

 

Color Space?

We get asked quite often if we can provide a profile for the camera. The short answer is that it's not necessary, here's why. Each device, monitor, printer, film etc. is capable of producing only a part of the colors the human eye can perceive. This is called the color gamut of the device. The color gamut of a printer covers less color space than most monitors, so profiles are calculated to eliminate, limit or adjust the colors displayed on the monitor so they will closely match the color gamut of the output device and what you see will match what is printed. Film has the capability to produce every color you see on the monitor, and therefore no color profile is needed. This concept is illustrated by the chromaticity diagram shown here.

 

 

Because film has this capacity it is best to use the color space which reproduces the most colors on your monitor. Adobe RGB or sRGB would be our recommendation. Very few displays are capable of displaying more than the sRGB color space, so if your display is calibrated, and you can see the steps in the gray bar above, the slides you get back will look just like your screen when viewed correctly.

 

---

Formats:

When we receive a file we will preview and convert it before shooting. We convert the files to RLE compressed TARGA files, and during the conversion we also add borders if necessary to avoid cropping in the slide mount, and pre-rotate images if necessary. We let the camera hardware take care of scaling requirements to fit the image to the film frame.

 

You may specify any special instructions for borders, crop or format on the order form when you submit your order. We don't use postscript rip software for presentation programs because there are always potential problems with rip software. Instead we rasterize files to the physical resolution of the camera so they maintain the highest possible quality.

 

Whatever format you send, these are some rules for the best result:

For more detailed information on specific file formats please refer to our Format page.

---

Viewing Slides?

People have complained that color didn't match when they held the digital slide up to the window, or a wall. This is often the weak link in the chain. When you look at the slides and compare them to your display you should make sure you are using a color correct light source. Viewing conditions are detailed in ANSI Standard PH2.30-1989. The basics of this standard are:

 

If you don't have a viewer that meets these standards you may feel that the color does not match, and there won't be much we can do about it. Suitable illuminators are available from just about any supplier of photographic products.

---

Digital Cameras?

The most common question is: "Will my camera produce a good enough file for a slide?" The answer is: "YES" Just about all digital cameras these days will provide files that make great slides. Anything above 2 MPixels will look better than it does on your monitor. For best results, use the highest resolution, and capture the image in medium or high quality JPEG format. If you plan to edit the image in PhotoShop or some other image editing program, it would be best to capture the image in either RAW or TIF format. After editing the image save it in high quality JPEG format to send to us.

 

Most digital cameras capture images in a slightly different aspect ratio than a full frame slide. What this means is that when you have slides made from an unedited digital camera photo, the slide will have a small black border on the edges, like the one shown at the right. If you want the image to fill the full mount without borders, crop the image in a 2:3 aspect ratio. (2:3 is the same ratio as a 4x6 inch print.)

 

---

• Back to top

 

---

What we don't charge for:

---

Cut-off and shipping

We make every effort to begin every job as it arrives, and ship it as fast as we can, but we will not ship any order that does not meet our quality standards. If you have tight time requirements please call us to confirm the schedule. Below is a chart of cut-off times which you may find helpful.

 

Cut off times in your time zone:
Orders will be shipped on the next business day if files are received by:		1:00PM	2:00PM	3:00PM	4:00PM
Shipping Rates
1st Class Mail:	$2.50	3-6 day delivery - no tracking
Priority Mail:	$6.00	3-5 day delivery - no tracking
Fed Ex Express Saver:	$12.50	3 business days or less with tracking
Fed Ex 2-Day:	$17.50	2nd business day delivery with tracking
Fed Ex Next Day:	$25.00	Next business day delivery with tracking
Fed Ex Priority:	$30.00	Next business morning before 10:30 with tracking
Fed Ex Saturday:	$42.50	For Emergencies
International Mail:	$14.00	Most Countries - no tracking
International Fed Ex:	$42.50	Canada, Europe & Asia with tracking

• Back to top