# UNCALIBRATED IMAGES **URL:** \ **Category:** PIX4Dmapper Questions/Troubleshooting\ **Created:** [January 13, 2018, 5:04am UTC](https://community.pix4d.com/t/uncalibrated-images/4376 "2018-01-13T05:04:57Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![MOHAN\_KUMAR](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@MOHAN\_KUMAR](https://community.pix4d.com/u/MOHAN_KUMAR)\ **Post date:** [January 13, 2018, 5:04am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/1 "2018-01-13T05:04:57Z")
WHAT IS THE REASON BEHIND IMAGE COULDN’T CALIBRATE…please explain ---
**Author:** ![Selim\_Erguden](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/selim_erguden/32/337_2.png) [@Selim\_Erguden](https://community.pix4d.com/u/Selim_Erguden)\ **Post date:** [January 13, 2018, 2:02pm UTC](https://community.pix4d.com/t/uncalibrated-images/4376/2 "2018-01-13T14:02:11Z")
Hey Mohan, There may be a lot of reasons why your images couldn’t calibrate. It could be an overlap issue, it could be the surface that you are trying to image(dense vegetation, water or snow etc…)or it could be the Pix4D settings that you were using. If you could take a screenshot of your Quality I may be able to help you more. ---
**Author:** ![MOHAN\_KUMAR](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@MOHAN\_KUMAR](https://community.pix4d.com/u/MOHAN_KUMAR)\ **Post date:** [January 16, 2018, 10:35am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/3 "2018-01-16T10:35:38Z")
hey selim thank you, tell me gcp position also affects right, is that so pls help with this question in my new post: [https://support.pix4d.com/hc/en-us/articles/hc/en-us/community/posts/360000006826-gcp-loction](https://support.pix4d.com/hc/en-us/articles/hc/en-us/community/posts/360000006826-gcp-loction) ---
**Author:** ![Selim\_Erguden](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/selim_erguden/32/337_2.png) [@Selim\_Erguden](https://community.pix4d.com/u/Selim_Erguden)\ **Post date:** [January 16, 2018, 8:23pm UTC](https://community.pix4d.com/t/uncalibrated-images/4376/4 "2018-01-16T20:23:35Z")
Hey Mohan, GCP’s would definitely affect the the overall quality of your final product. However GCP’s are inputted  mostly after step 1 is done. Then you re-optimize it so I am not sure if GCP’s would affect how many images are being calibrated since calibration is done prior to GCP implementation. You may however implement the GCP’s after step 1 is done then re-process step 1 to see if you would get more images calibrated. ---
**Author:** ![MOHAN\_KUMAR](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@MOHAN\_KUMAR](https://community.pix4d.com/u/MOHAN_KUMAR)\ **Post date:** [January 17, 2018, 5:05am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/5 "2018-01-17T05:05:53Z")
hey selim,  ok i agree with, and tell me weather our gcp are laid at good position or not. See those picture i have sent you. ---
**Author:** ![Selim\_Erguden](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/selim_erguden/32/337_2.png) [@Selim\_Erguden](https://community.pix4d.com/u/Selim_Erguden)\ **Post date:** [January 17, 2018, 3:46pm UTC](https://community.pix4d.com/t/uncalibrated-images/4376/6 "2018-01-17T15:46:08Z")
Hey Mohan, Please take a look at the following link for the GCP distribution and positioning.  [https://support.pix4d.com/hc/en-us/articles/202557489#label1&gsc.tab=0](https://support.pix4d.com/hc/en-us/articles/202557489#label1&gsc.tab=0) ---
**Author:** ![MOHAN\_KUMAR](https://avatars.discourse-cdn.com/v4/letter/m/e8c25b/32.png) [@MOHAN\_KUMAR](https://community.pix4d.com/u/MOHAN_KUMAR)\ **Post date:** [January 18, 2018, 6:12am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/7 "2018-01-18T06:12:15Z")
hey selim, here is the screen shots of quality report of our project. ---
**Author:** ![Selim\_Erguden](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/selim_erguden/32/337_2.png) [@Selim\_Erguden](https://community.pix4d.com/u/Selim_Erguden)\ **Post date:** [January 18, 2018, 1:56pm UTC](https://community.pix4d.com/t/uncalibrated-images/4376/8 "2018-01-18T13:56:36Z")
Hey Mohan, Your uncalibrated images are in a dense forested area so you should try half image scale (0.5) and Alternative Calibration method. You may be able to get more images calibrated. ---
**Author:** ![Kurt\_Meinders](https://avatars.discourse-cdn.com/v4/letter/k/b3f665/32.png) [@Kurt\_Meinders](https://community.pix4d.com/u/Kurt_Meinders)\ **Post date:** [December 18, 2018, 12:14am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/9 "2018-12-18T00:14:29Z")
Selim, Is there a support source that explains how to do half image scale.   I have the same issue.   ---
**Author:** ![Blaz](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/blaz/32/4344_2.png) [@Blaz](https://community.pix4d.com/u/Blaz)\ **Post date:** [December 18, 2018, 6:53am UTC](https://community.pix4d.com/t/uncalibrated-images/4376/10 "2018-12-18T06:53:06Z")
@Kurt, Selim is referring to the processing option in Step 1. called [keypoints Image Scale ](https://support.pix4d.com/hc/en-us/articles/202557759#label3)which defines the image size used to extract the keypoints. I also recommend checking [How to improve the outputs of dense vegetation areas?](https://support.pix4d.com/hc/en-us/articles/202560159-) article for more information.