Why would DigitalGlobe not provide gains and offsets with the data so you can calibrate it? In the WV-3 data that I have worked with, they do provide this information in the .IMD files:
absCalFactor = 1.432870e-02;
effectiveBandwidth = 4.050000e-02;

ENVI will use this information to perform the Radiometric Calibration if you open the data using the .TIL file.

If your data do not have the gain and offset information to perform Radiometric Calibration, I wold ask DG to provide it like other data providers do. I have also run across some of their calibration information here:
https://dg-cms-uploads-production.s3.amazonaws.com/uploads/document/file/207/Radiometric_Use_of_WorldView-3_v2.pdf

You can then save your data as ENVI format and use View Metadata->Edit Metadata and add in the gains and offset values to the header so the data can be calibrated to radiance. You will also need the Irradiance values and Earth-sun distance if you want to calibrate to TOA reflectance.

Thank you for the reply!

I opened the .TIL image using open as-> optical sensors -> Digital Globe -> World View 3. My metadata file have absCalFactor = -9.990000e+02 and effectiveBandwidth = 3.810000e-02. But in the metadata -> spectral table, radiance gains, reflectance gains, reflectance offset and bad bands fields are empty. It only has values for radiance offsets and Irradiance. When I try to perform the radiometric correction, it sends me an error message saying "Calibration requires gain and offset for each band".

I contacted the re-seller where we bought the image and they resend the images three times, but the images were all same. I also contacted DG directly and their reply said "There is no calibration issues. As I mentioned before .imd files doesn't include gain and offset values, they are auto generated with the same format for every order."

The calibration information you send have some values for gain and offset, I'll try to enter them into the image file as you instructed, hopefully it will work.. But I do not understand and just so curious why these values do not automatically appear in the metadata as other sensors do..

I think it would be a good idea to have a look at the product you received. Perhaps there was a change in format and ENVI is unable to read the calibration information.
Could you please submit this question through support services? If you are a student using a lab license, it should be submitted by the license administrator.
Alternatively, if you have or know the gains and offsets to use, I would save the file to ENVI format and add the information to the header as described previously. This may be the work around if there is an issue reading the metadata.

Hi, Thank you so much your your advise. I was able to get DRA off, 16 bit product and it works perfectly for the radiometric correction. But I am having a new trouble now. My image have 8 bands (coastal blue, blue, green, yellow, red, red edge, NIR 1 and NIR2), no SWIR bands. So I can not perform the FLAASH correction. I tried QUAC correction as WV2, RGB, NIR and Landsat options as it does not provide option for WV3. But every time, I get blank pixels in the output, it appears like wholes in the image. It is worst when I used WV2 option. Is there any other atm correction method or option in QUAC correction that might work for this dataset? Thank you!

You can still process the data in FLAASH using Multispectral Settings. You will not be able to calculate aerosols or do a water retrieval so those should be off.
For QUac, you can use Unknown sensor. Be sure to create a mask of background pixels and use it when processing in FLAASH. If you do not, the background will be considered an endmember and can affect the results.

Hi, Thank you for your reply. I was able to process FLAASH without aerosol retrieval, but still there are lots of blank pixels, I just noticed that some blank pixels are created during the radiometric correction as well. Then there are lots of blank pixels after the atmospheric correction. I tried to apply a blank pixel mask, but FLAASH did not give the option to apply mask. I tried to use mask for the QUAC correction and process as unknown sensor. But it gives me error message saying it can't extract the endmembers and ask to try a different sensor. I tried several other options, but received the same error message. Can you please help me to fix this problem? Thank you!

What do you mean by 'blank'? If you put your cursor over one of these pixels, what value does it show? It is possible that they are negative or very low. This occurs frequently in areas of water and shadow. Can you calculate and post the basic statistics of the result from Radiometric Calibration (using FLAASH Settings) and then after FLAASH correction?

When opened true color, the cursor value shows as 'No Data' for all 8 bands after the radiometric correction. They appear as holes in the image. Most of these pixels are in shaded areas and few in water.
Basic stat after radiometric correction:
Min Max Mean StdDev
Band 1 0.009543 60.408104 0.644900 1.085968
Band 2 0.001946 62.044239 1.204353 1.297036
Band 3 0.015647 40.522682 1.600582 1.074362
Band 4 0.016796 34.853352 1.458623 1.078179
Band 5 0.012294 49.201557 1.735617 1.628500
Band 6 0.016195 33.391163 5.387143 1.929354
Band 7 0.006135 33.457809 10.306771 3.883123
Band 8 0.007536 24.913122 8.170882 2.852122

After the FLAASH correction, there are more of these pixels, but they appear in blue color. Cursor value is 0 for all 8 bands. All most all the shaded pixels and most of the water pixels have 0 after the FLAASH.
Basic stat after the FLAASH correction:
Min Max Mean StdDev
Band 1 -2235 24847 -1552.295251 535.641585
Band 2 -1310 17972 -784.258209 357.980847
Band 3 -851 11483 -300.630367 262.516010
Band 4 -598 10214 -138.393889 256.406434
Band 5 -508 15120 4.129498 385.559903
Band 6 -584 12530 1335.838476 803.633796
Band 7 -707 13455 3498.917128 1870.665882
Band 8 -664 15441 4359.234572 2172.485202

Your means after FLAASH correction are mostly negative. Can you post your template.txt that is created after FLAASH processing?

Below is the template.txt file;
;
;ENVI FLAASH PARAMETERS TEMPLATE (5.4.1)
;Written Tue Dec 19 14:35:13 2017
;
; Project Parameters
enviacc.prj.radiance_file = I:\Worldview 3 new data\processed\preprocessing_Dec_2017\radiometric_correction.dat
enviacc.prj.reflect_file = I:\Worldview 3 new data\processed\preprocessing_Dec_2017\FLAASH_correction2
enviacc.prj.filter_func_file = C:\Program Files\Harris\ENVI54\classic\filt_func\worldview3.sli
enviacc.prj.filter_func_file_index = 1
enviacc.prj.water_band_choice = 1.13
enviacc.prj.red_channel = 5
enviacc.prj.green_channel = 3
enviacc.prj.blue_channel = 1
enviacc.prj.water_abs_channel = 0
enviacc.prj.water_ref_channel = 0
enviacc.prj.kt_upper_channel = 0
enviacc.prj.kt_lower_channel = 5
enviacc.prj.kt_cutoff = 0.0800
enviacc.prj.kt_ratio = 0.5000
enviacc.prj.cirrus_channel = 0
enviacc.prj.water_retrieval = 0
enviacc.prj.modtran_directory = I:\Worldview 3 new data\processed\preprocessing_Dec_2017\New folder\
;
; MODTRAN Parameters
enviacc.modtran.visvalue = 40.0000
enviacc.modtran.f_resolution = 5.0000
enviacc.modtran.day = 12
enviacc.modtran.month = 7
enviacc.modtran.year = 2016
enviacc.modtran.gmt = 16.6106
enviacc.modtran.latitude = 42.7668
enviacc.modtran.longitude = -80.5959
enviacc.modtran.sensor_altitude = 617.0000
enviacc.modtran.ground_elevation = 0.0000
enviacc.modtran.view_zenith_angle = 180.0000
enviacc.modtran.view_azimuth = 0.0000
enviacc.modtran.atmosphere_model = 2
enviacc.modtran.aerosol_model = 1
enviacc.modtran.multiscatter_model = 2
enviacc.modtran.disort_streams = 8
enviacc.modtran.co2mix = 390.0000
enviacc.modtran.water_column_multiplier = 1.0000
;
; Image Parameters
enviacc.img.nspatial = 3795
enviacc.img.nlines = 2773
enviacc.img.data_type = 4
enviacc.img.margin1 = 0
enviacc.img.margin2 = 0
enviacc.img.nskip = 0
enviacc.img.pixel_size = 0.8800
enviacc.img.sensor_name = WorldView-3
;
; Analysis Parameters
enviacc.ana.aerosol_scaleht = 1.5000
enviacc.ana.use_adjacency = 1
enviacc.ana.output_scale = 10000.0000
enviacc.ana.output_diagnostic_files = 0
enviacc.ana.auto_save_template = 1
enviacc.ana.polishing_res = 9
enviacc.ana.aerosol_retrieval = 0
enviacc.ana.calc_wl_correction = 0
enviacc.ana.reuse_modtran_calcs = 0
enviacc.ana.use_square_slit_function = 0
enviacc.ana.convolution_method = fft
enviacc.ana.use_tiling = 1
enviacc.ana.tile_size = 100.0000
;
; GParameters Parameters
enviacc.gparameters.gfact = 0
enviacc.gparameters.gval = 0.0000
enviacc.gparameters.use_lr_method = 0
enviacc.gparameters.multikernel = 1
enviacc.gparameters.autoroi = auto
enviacc.gparameters.selarg = a
;
; Spectral Parameters
enviacc.spc.wavelength_units = nanometer
enviacc.spc.lambda = [
425.0000, 480.0000, 545.0000, 605.0000, 660.0000, 725.0000, 832.5000,
950.0000]
enviacc.spc.fwhm = [
50.000000, 60.000000, 70.000000, 40.000000, 60.000000, 40.000000, 125.000000,
180.000000]
enviacc.img.p_input_scale = [
1.0000, 1.0000, 1.0000, 1.0000, 1.0000, 1.0000, 1.0000,
1.0000]

You have me stumped without having access to the data. It is not unusual that you have negative values in your FLAASH results in dark areas so it might be correct. I just don't see anything inherently wrong in your FLAASH settings or input stats. Your output stat means look very low in the first few bands. If your image looks fairly clear without a lot of water vapor or haze, you might try setting the Initial visibility to 80-100km to boost the visible bands.
You mentioned you would get an error in Quac regarding the inability to find enough endmembers in the image. Is your image very homogeneous? Quac does require that an image have a minimum of 10 unique materials to characterize the image accurately.

My image is very clear, no visible haze at all and covers a large area, So I always tried to do a smaller area to save processing time. I tried everything you suggested, it reduced the No Data and 0 value pixels, but I still had loads of them.. I was able to use QUAC when I used the entire image, but there were many No Data pixels (more than 80% of the image).

I managed to do something, but I am not sure whether that method is acceptable. I checked the shadow areas and they have very low pixel values in the original image. So I multiplied the entire image by 10 using band math (float (b1)*10). Then transferred gain and offset from the original image to the resultant image and did radiometric correction with FLAASH settings. Then did FLAASH correction with initial visibility of 40 km. There is no more No data or 0 value pixels in the image and it looks so good! The histograms after the FLAASH is little weird though, below are the basic stat;
Basic Stats Min Max Mean StdDev
Band 1 -32768 32767 2188.468643 3274.561761
Band 2 -32768 32767 2472.035491 3252.697032
Band 3 -32768 32767 3406.993476 2913.007473
Band 4 -32768 32767 3561.009254 3400.422862
Band 5 -32768 32767 5330.570552 5767.738096
Band 6 -32768 32767 13907.716940 6676.264984
Band 7 -32768 32767 -686.028568 22913.114711
Band 8 -32768 32767 -4222.349394 22408.476623

Is this method correct/accepable?
I know it is really hard to help me without the data. Unfortunately, I can not send the data files and the forum do not allow me to add any screenshots, I can email you if you like to check. I really appreciate all your help and suggestions! Thank you.

I would not boost the pixel values before FLAASH correction. FLAASH expects specific physical units of microW/(sr*cm^2*nm) and the output pixel values can be poorly modeled if you do not use the correct units. If you can submit your question through a POC at your institution, it may be best to work with your data directly.

That is so unfortunate.. I am not sure who is POC in my university. But the lisence administrator is my my supervisor. I'll send an email through her. Thank you!

I'm sorry, I forgot to mention in my previeous reply, is it same for thr QUAC correction? QUAC also works well after multiplying the image with 10.

No, you can provide DN, radiance or even TOA reflectance to Quac for correction. A boost of 10x should not affect it in a similar way.

Thank you so much! My image is doing great with the QUAC. I really appreciate your help.

Hello, I read the conversation because I have the same problem with my WV3 images. But, I would like to confirm if my understood about the solution is the correct one please: Using my original images (they are in DN values) I have to create a mask for background pixels and then apply QUAC using unknown sensor option. So, I do not have to run a radiometric calibration before using Flaash settings, right?
Furthermore, if I want to do a pan sharpening, can I use the result obtained after applying QUAC?
Finally, I have WV3, WV2 and GE1 images and I was wondering if I can apply the same solution for all my images.
Thank you in advance for your help!

You do not have to run Radiometric Calibration. However, I think it is good practice to convert the data to radiance using FLAASH Settings and run both FLAASH and Quac on the data to compare results. You are correct that when using Quac, it is important to use a mask on background pixels. FLAASH is not affected by the background pixels so it is not necessary for that tool.
For Pan sharpening, I would use the results from Quac but do realize that pan sharpening affects the reflectance values so if you are most concerned with spectral integrity, it is best to do analysis on products that are not pan sharpened.
Yes, you can use a similar process on other images as well. If you do not see your sensor listed in Quac, you can use Unknown.